A sharp pain shot through Rex and he instinctively reached up to clutch his heart, almost tearing at his t-shirt.
Rex stopped where he was and slid down to the floor in pain.
A buzzing noise pounded at his head and Rex shoved his head between his legs, trying to block out the noise that was assaulting his head.
"Are you okay, mijo?" A concerned voice broke through the pain.
Rex cracked one of his eyes open to see Caesar looking down at him, tearing his attention from the clipboard he'd been frantically scribbling on during the brothers' walk to where Rex was curled up on the ground.
"The noise is back," Rex groaned out, clenching his teeth from the overwhelming buzzing.
Caesar frowned and clipped his clipboard to his belt, before bending himself over to pick up Rex. Caesar struggled as he wrapped his arms around Rex's body and attempted to lift him straight up.
Caesar was not known for his strength and it took him two tries and almost dropping Rex before he was able to heft Rex up into his arms.
With a grunt, Caesar started jogging down to the end of the hall they had just come out of and towards the greenhouse.
"What are you doing, Caesar? Stop that, my head hurts!" Rex yelled out. He banged his fists on Caesar's back, begging him to stop running.
"I'm just testing out a theory I have about the noise you keep hearing," Caesar yelled back to Rex.
"I don't care!" Rex cried. "You're jostling me around and it's making my headache worse, seriously st-"
Rex abruptly stopped his yelling as Caesar finally reached the end of the hallway and crossed the threshold into the greenhouse, where suddenly the pain in his head ceased.
"Oh," Rex said simply, his voice slightly hoarse. "The noise stopped."
Caesar plopped him back on the ground, panting heavily.
Rex looked around in bewilderment and wide eyes, wondering how Caesar knew moving him from the hallway and into the greenhouse would stop the noise. The air felt different here, less thick despite the heavy mist that rolled through the room, and for it was the quietest room Rex has been in since his accident.
"Hmmm, just as I suspected," Caesar muttered, still out of breath. "The nanites we used to save your life must have made you more sensitive to the mechanical noises machines make. Young children are already sensitive to the higher frequencies some machines emit. There are significantly fewer machines here in the greenhouse than in the lab. Here, let me see your eyes for a second?"
Rex turned towards Caesar and he let Caesar tilt his head upwards towards the greenhouse's light fixtures.
Caesar shined a small penlight into both of Rex's eyes.
Inside Rex's pupil, a subtle movement of metal could be seen. Enough nanites had replicated inside Rex that Caesar could observe the nanites from Rex's pupil instead of drawing blood to study Rex's nanites.
The nanites were active and Caesar noticed some were glowing, indicating they were active in Rex's body, which was odd.
The nanites were only supposed to be active when they were healing Rex of his injuries, not when Rex was perfectly healthy. The batch of nanites that had been installed in Rex to save him was not of the variety that could do anything but heal so it was odd that they would be active right now.
However, Caesar mused, this did explain Rex's changing behavior over the last couple of weeks.
The activation of the nanites was probably the cause of Rex's string of recent sensitivities, which explained the grumblings of pain whenever Rex walked into the labs, the auditory hallucinations Rex had been having late at night, his complaints about his muscles aching.
As Caesar thought about it more, he probably should have noticed sooner the nanites were still active. For heaven's sake, Rex had accidentally yanked a pot of boiling water off the stove and onto himself and he hadn't felt the pain of the burns he'd received and he was fully healed just days later!
Something must have tripped up in the nanites programming, leaving them constantly activated and the constant thrum of the nanites have been messing with Rex, instantly healing even the slightest injury and messing with Rex's senses.
He'd have to have run tests later to see the full extent of damage and to reprogram the nanites' A.I. program in Rex.
Caesar sighed, glad he'd figured out what was wrong with Rex, and stopped shining his penlight into Rex's eyes.
"Well, mijo, I'm gonna have to schedule another check-up later today, I think your nanites are messing with your hearing and making you extra sensitive. Usually, you'd just have to wait until you're old enough your ears will have lost the high pitched range, but you know how you've said you've been hearing voices?"
"Yeah?" Rex asked.
"Well those are auditory hallucinations and sometimes they're caused by stress, and I think the high-pitched noises are stressing you out."
Rex nodded and Caesar grabbed Rex's hand.
"Here, let's take the long way around to the cafeteria! Or if you want, I made a machine that also makes a really good smoothie."
"Mom, is this gonna hurt?" Rex asked in a small voice, clutching onto his mother's lab coat sleeve.
Rex was sat on an examination table in the testing lab, dressed up in a white hospital gown. He had some kind of contraption strapped onto his head, one that Rex had increasingly become familiar with in the past few weeks since his injury.
"Only a little bit, Rex," his mother said. She patted Rex in a comforting way. "We need to rework nanites and unfortunately we'll need to test and make sure they aren't hurting you anymore. It won't be any worse than what you've felt before. I'll sit right here next to you, ok baby?"
"M'kay."
Rex let go of his mother's sleeve in favor of wringing out his hands and watching the scientists in the room with him.
It had been a decided rule that Rex's parents and brother weren't allowed to directly work with Rex as the scientists gathered information from Rex's nanites. Rex's mother and father were allowed to be in the room to be emotional support for Rex, and they were allowed to assist the others they checked to make sure Rex's mobility and normal cognitive skills were unchanged, but they weren't allowed to actually run any studies.
Caesar was allowed to oversee and reprogram Rex's nanites, but he was in another room that was separated from the one Rex was in because the equipment to do so was not easily movable.
A scientist, Dr. Falchi Rex thinks, signals to his mom that the testing was about to begin.
Rex closed his eyes as the machine on his head whirled to life and the buzzing in his head started up again.
The scientists yelled something out about frequencies and the noise got higher pitched and the buzzing in his head changed as the frequency of the noise changed.
As the scientists furiously started scribbling down numbers and pictures were taken, a foreign presence was made known to Rex in his mind.
Each clack of the keyboard was a note and the whirring of the machine strapped to his head was an annoying murmur of voices that kept getting louder and louder and a voice in his head kept answering.
There was a sudden pop in Rex's head, just like when the air pressure changed in an airplane and the murmuring in his head expanded and suddenly the voices were yelling.
He wanted the voices to stop yelling, they wanted the voices to stop yelling, stop yelling, stop it, stop it!
"Grahhghhh!" Rex yelled and he tugged on the voices. He swore he could see a giant off switch for the voices and he reached out and hastily flipped it.
Blue flooded his vision and his veins glowed and traveled up his face as the machine on his head whirred off.
Rex reached up and threw the machine on the floor where it shattered into neat chunks as if it was a sliced apple.
Heavily gasping, Rex stared into the surprised faces of everyone in the room.
Rex's eyes were still glowing a toxic blue as the blue in his veins faded out.
Dr. Falchi slowly walked up to the remains of the machine and picked up its battery. Fully charged when they first had put it on Rex at the beginning of this appointment, Dr. Falchi flipped it over to reveal it was totally drained.
"I'm sorry, I-I didn't mean to do that!" Rex stuttered out, teeth clattering together, expecting the scientists to start berating him.
Instead, they all looked at him with wonder and excitement in their eyes.