It'd been 5 hours since Sherlock had launched himself from the taxi, when he arrived back at 221B that evening.
He ran straight to his bedroom, slamming the door closed, leaving a confused John staring after him not for the first time that day.
He had some thinking to do, but he wasn't sure that he could sort out his thoughts sat in the living room under John's scrutiny. John would surely want to know where Sherlock had been, and he was not in the mood for such mundane questions. Boring. He knew John wouldn't bother calling after him when he was in one of these moods.
As he lay on the bed, his heart pounded. He could hear his pulse thumping in his ears and feel the blood rushing through his veins. He took a few deep, calming breaths and attempted to collect his thoughts. He spent time trying to rationalise his feelings.
Why did he feel this way?
John was his friend? Sherlock wasn't sure, but he thought that the 'relationship' between them (he used the word carefully, even in his head) fell into the category of friends.
Not having had any previous experiences with friendship, aside from the semi-professional/semi-friendship he had with Greg, Sherlock wondered if his confusing feelings were normal.
Maybe he was making too much of it. Perhaps all friends felt this way and just the newness of it had intensified the effect for Sherlock?
He frowned and closed his eyes. No, that's not what this is, he thought. This is something else. Something more. He knew he was trying to convince himself that this was just the way friends felt, but that wasn't right at all.
Maybe he should discuss this with John?
John had never judged him in the past. He was tolerant and patient with Sherlock, far more so than anybody else in Sherlock's life. John had listened and helped before, when Sherlock had been confused by his feelings or how he should be acting. John was sensible and rational to Sherlock's impulsive. John would have the answers.
Except he couldn't ask John about this. He couldn't say "John, I feel this way about you", could he?
How would his flatmate; friend; colleague feel about Sherlock telling him that every time he walked into the room, he felt the compulsion to touch him; to hold him; to never let him go?
How would straight; not gay; 'not his date' John feel about that?
Sherlock thought back to where he'd been that afternoon.
Yes, there was only one way to deal with this.
He jumped up from the bed and began to plan it out.