As John stood there Sherlock stirred slightly and a rough, dry cough escaped him, and John's eyebrows rose.
Okay... That might just be what had woken him earlier...
He moved closer and laid a hand on the detective's forehead-and then drew it back with a huff, muttering under his breath, "Jesus, Sherlock... You're burning up..."
He had just taken it as moodiness when he had last seen him, but now with the cough and fever mixed in John realised that he did look rather miserable, curled there on the sofa, locked in a fitful sleep. The last thing John wanted to do was wake him, for both their sakes-but he knew he needed to.
"Sherlock." He shook him gently by the shoulder, speaking softly. "Sherlock, wake up. I need to take your temperature."
He was met with a low groan, and Sherlock's eyes fluttered open. It took a moment for him to focus and wake up fully, but when he did he let his head roll back with a heavy exhale of distress.
"I'm sorry... I'll just get the thermometer and be right back, okay?" John straightened up, waiting in vain for a reply, and then padded off to the bathroom.
He poked about in the medicine cabinet a while, hoping against hope that Sherlock hadn't seen fit to use the thermometer for some disgusting experiment, of course neglecting the fact that one day they'd actually have need of it. Fortunately, though, he eventually found it hiding behind a box of gauze, and was soon back by the detective's bedside.
Sherlock had curled up further, tucking his coat up to his chin. He looked up at John with weary eyes, watching him mutely.
"Okay. Open up." John held out the thermometer, and Sherlock gazed at it for a moment before he accepted it.
"J'hn..."
"Hush, don't talk, you'll mess up the readout." When it finally beeped John retrieved it and busied himself analysing the numbers, and a frown creased his brow. "38.3C..."
Sherlock drew in another scratchy breath, but it caught in his throat and he was wracked with another bout of coughs.
"I'll get you some water, alright?" John was soon back with a fresh glass, handing it to the detective carefully to make sure he didn't spill any.
When at last Sherlock was settled back again, John began his doctor's interrogation.
"Aside from the fever, how are you feeling? Symptoms?"
Sherlock's voice was hoarse and thick, and he pulled his coat tighter around himself. "Cold..."
"Okay, chills. What else? Headache?"
Sherlock nodded. "Mmhm..."
"How about body aches? Sore throat?"
"Everything hurts..."
John nodded, rocking back on his heels. "Sounds like the flu alright."
Sherlock just looked up at him, eyes narrowing dubiously. "...I don't get the flu."
"Well then, I'll just go back to bed. If you don't get the flu, then what am I doing up taking care of you?" John's brows arched sarcastically, but he made no move to go to bed.
Instead he left Sherlock to brood quietly while he fetched a few blankets from the hall closet, and came back to arrange them around the detective's shoulders. He smiled slightly, but pretended he hadn't heard the little sigh of relief that left Sherlock's lips as he nestled deeper into his new cocoon of warm blankets and couch cushions.
"We really should get you changed out of your coat and jacket..."
But Sherlock shook his head. "Too cold."
John hesitated, but decided to let it go for now. Rest would be the best thing for it, in the meantime.
"Do you need anything else? Tea, maybe?"