Several hours later, he woke to the sound of the captain calling his name.
"Spock, Spo..."
"Captain! Are you alright?"
"I feel... tired."
"That's to be expected, captain. I believe that you have an infection. I have yet to determine what infected you, or how to treat it."
"You're my science officer, you're supposed to find out. You're supposed to have the answers."
"I'm quite aware of my responsibilities. Currently, since you are no longer fit for duty, I am taking command of this mission. I need to get you back to the ship. I'm not sure how. I'm just... not sure."
Spock massaged his forehead. He had never been so uncertain, or been really affected by a mission.
"You appear to be emotionally compromised, Spock, so neither of us can be in command according to regulations. Therefore, we'll just have to be as innovative as possible in finding solutions, with both of us contributing. We'll make decisions together."
Spock nodded silently, wondering if there was more to it than his emotions. If he wasn't capable of controlling his emotions, then something must be wrong with him physically. Was he ill, too? Was he really incapable of command of himself, let alone anything or anyone else?

Spock wished that he could just send a blood sample to one of the ship's labs to determine what the infectious agent causing Kirk's [and possibly his own] illness, was. He needed to know what to do, how to treat it; whatever 'it' was.
He was afraid, for once. He tried to suppress his emotion, and succeeded to some extent. He checked himself for symptoms of illness and made several types of antibodies, similar to the type that would probably have evolved in this climate, after the climate change several hundred years ago. He then searched for the pathogen in his bloodstream. He found it and sent a few antibodies to fight it. He was distracted when an arrow flew from the depths of the forest, and hit his left iliac region, near one of the Vulcan's major arteries. Another flew and hit Spock's right thigh.
"Ca-captain. I require assista..."
Spock's eyes rolled back into his head and he collapsed, the blood now seeping out beyond his control.
"Spock!"
Kirk came towards Spock, who was now gasping for breath, holding his side, near his heart. He was dying, both of them knew that, but Kirk was in denial.
Kirk maintained enough of his wits to realize that if two arrows had hit Spock, there could be more of the creatures approaching, but shockingly none came. Kirk presumed Spock's injuries were merely accidental.
"Captain. I have discovered the location of the com-communications barrier. It is no-not far from here, approximately half a mile away. Destroy the device. It will allow others to be more sa-safe here in the future. Go. It is only lo-logical."
"I can't just let you bleed out. You're my first officer, and you're my friend. I can't do that."
"Jim, it is necessary. I will die in several minutes. Consider it a last request."
Kirk was glassy-eyed, with one tear running down his cheek.
"I can-can't- I ju-just..."
"Jim. You must g-go. I have little time left."
"Okay."
Jim hugged Spock, wincing as his newly-regenerated ribs were squeezed a little too hard. The tears flowed freely as he noted the weakness of Spock's reciprocation of the hug. He lowered Spock again then smoothed his hair into place, how it always looked when he sat at his station or leaned over his scanner. He smiled then took off running, leaving Spock alone.

Kirk ran, as fast as he could. He realized the logic behind Spock's suggestion. He would not only secure the safety of future visitors, but possibly save his own life. Kirk needed that little assurance to press on harder.
Within a few minutes, he had reached the device. Ironically, it had been near the banana plant as he had suspected. Obvious, nearby, just like Spock said. He took out his phaser, set it to maximum, and used his last blast to destroy what was, to him, a huge piece of rubbish that was indirectly allowing his best friend to die. As soon as he was sure that the device was thoroughly 'dead', he ran back.
When Kirk arrived, he found Spock, reclining holding the communicator.
"Spock to Enterprise,"
Only static replied. Spock appeared nearly frustrated, then it passed and he lay back, seemingly resigned to his fate.
"Uhura here."
"Spock here. Two to beam unh..."
Spock passed out.
"Spock? Are you there? Are you reading me? SPOCK!"
"Uhura, Kirk here. Spock is unconscious. By his calculations, he has little time left. We need a medical team in the transporter room and we need to be beamed up. Understood?"
"Yes, sir."

Kirk picked up Spock, holding him in his arms, awaiting the transporter effect. When it came ten seconds later, he stepped off the transporter pad and laid Spock on the waiting gurney.
"Get him to sickbay, NOW!"
McCoy and the other medical personnel scurried around, positioning themselves for the race to sickbay.
Scotty called for deck five to be cleared, and for sickbay to be ready.
The medical technicians rushed there, Kirk staying a few feet behind. He was distraught, no longer crying but still extremely emotional. He knew that his emotional status would not expedite Spock's recovery, but he still felt this way due to his inability to control his emotions to the point that Spock could due to the lack of mental disciplines in his education. He felt empty, yet anxious, yet guilty for something beyond his control.
Kirk stepped in the sickbay, coming back to himself after a few moments of contemplation.
He watched, from his hazy perspective, as Spock's boots were removed, and his blood-soaked uniform cut off.
He was slowly led away by a nurse that Doctor McCoy had assigned to the duty of keeping the most annoying and inquisitive member of the crew out of his sickbay, unless bleeding or getting a physical. When the captain started to walk out while being treated, she hypo'd him, when he was plain bugging McCoy, she hypo'd him again. The only reason that the highly competent nurse had been assigned this duty was because McCoy wasted too much time without her, and her services were actually needed in this area.
For once, Kirk wasn't aggressive at the first sight of the nurse. He was too shocked, and didn't even object when the nurse led him to a biobed in the corner. He held up his hand, however, when she tried to hypo him. He staggered over to where Spock was laying. His Spock-induced haze would not relent until Spock was well, and reassuring himself that Spock was still there not only calmed him but also helped him slip out of the trance that he was in.
Kirk watched as both arrows were removed and more green flowed from the wounds. He still stood by as Spock was prepped for emergency surgery to repair the damage done by the arrows, and remained to observe over two hours of the surgery.
Finally, the nurse assigned to banish all annoying entities from sickbay tapped him on the shoulder and told him to get some rest, and yet he still remained, by the side of the man who was nearly his t'hy'la. He waited, and eventually found a chair where he could still observe.
Half an hour after sitting down, Kirk fell asleep. He was exhausted, and was still healing.
An hour after that, McCoy began to close and assigned a security guard to escort the captain out of sickbay, and chuckled.
"Well Spock, I guess we do have one thing in common..."

Although no one was probably aware of the fact other than himself, Spock was beginning to waken. He was unaware of his location at first, but heard Kirk's familiar snore and McCoy's voice giving out orders. Spock opened his eyes, not yet having entered a healing trance. He saw his brother, his friend; first when he woke.
"Jim,"
He barely rasped, but miraculously Kirk woke instantly. The security guard took this opportunity to attempt to drag Kirk out of sickbay. Kirk pushed him away and ordered him to return to his post or his quarters.
"Spock."
Their eyes met for a moment until Spock felt that he was slipping again from consciousness. Kirk went to grab Spock's hand, until he remembered the symbolism behind the action, and how the Vulcan was likely to interpret his intentions. He pulled back, instead bringing his chair near to sit by his brother as he slept, until he too drifted into oblivion.