A/N: This idea came to me at about 2am last night and wouldn't go away. I was almost tempted to get out of bed and turn on my laptop just to get it out of my head... almost. I was also a bit hesitant to actually write this because I was afraid that describing the symptoms would trigger one in me, as has actually happened in the past. Luckily, it didn't. Anyway, please enjoy...
Emotions cripple. They get in the way of pure reasoning, and Sherlock finds no use for them when he's trying to deduce. Because if he feels, then the emotions running through his mind detour him from avenging the unnecessary deaths or exonerating the innocent. So he pushes those feelings aside, leaving them for later. But they pile up and attack from within, and when they do, Sherlock has to concentrate his entire will into keeping them hidden from those who call him cold and unfeeling, because he isn't, but that's none of their business.
He can feel his chest constricting and his breathing becoming labored, and every muscle in his body just wants to jump out of his skin, but he has to finish explaining to Lestrade and any other nearby member of the policing force why their murderer is a five-foot tall man with a limp in his right leg, and he's forced to repeat himself, which he hates, because they just won't understand, and he feels like he's going to die. When Lestrade finally takes action based on Sherlock's words, Sherlock excuses himself with an overly extravagant flourish to his step, and all he wants to do is run outside and feel the cool air, but instead he only walks, though at a quickened pace, just so they won't notice the torment he's going through; and they don't because they never do. When he finally exits onto the street, he takes a few deep breaths, and that helps a bit. But he decides to walk a few blocks before hailing a cab.
John never notices, either. And Sherlock's glad for that because, even though he has told John that he is in no way a hero, John still looks at him in that way, that glint in his eye that shows how proud he is of anything Sherlock does that is considered meritorious by societal standards. And, truth be told, Sherlock likes it, likes feeling appreciated. But the problem is that heroes aren't supposed to have weaknesses, and he doesn't want John's gazes of appreciation to suddenly turn into looks of pity. Because if he ever lost John's respect... So when John is prattling on about Sarah and how he feels about her and his plans for their date tonight or something along those lines because Sherlock stopped listening ages ago and is instead mentally cataloging lists of poisons, separating ones with cures from ones with no known antidotes; and then suddenly the muscles in Sherlock's hands start to tighten and he stretches his fingers out as far as they can go, but it's still not enough. And he's tapping his foot and squirming in his seat on the sofa, but John misinterprets his actions as signs of boredom. So when John gets fed up with Sherlock and leaves the flat, Sherlock waits exactly two minutes until he's sure John's out of sight. In the next few moments, he's standing on the front stoop, breathing in the fresh air and taking slow sips out of a glass of cold water.
Looking back, it was a silly reason for why John finally found out and what actually triggered those irksome feelings of anxiousness that time around. That's what Sherlock gets for trying to do things that were considered 'normal' in human society; because flatmates that get along are supposed to ask how the other's day went, right? Sherlock was sitting on the sofa. John faced him in the armchair. He talked about work because he had been at the clinic all day. There were several flu patients, two broken bones, and one severed thumb. But Sarah had gone to a seminar the other day about anxiety disorders, and she had filled John in about what had been said. So now John is explaining to Sherlock about heart palpitations and fear of dying and a loss of control, and Sherlock wants to laugh at the irony, but he can't because he's suddenly sweating and his heart is racing and his hands feel numb, but he has no idea why. And this time, finally, John notices that Sherlock is trembling. "Are you alright, Sherlock?" he asks with a concerned expression on his face. And he's unsure as to why, maybe because John actually was the first person to ever ask if he was okay, but Sherlock actually shakes his head no, and he lets out a long, shaky breath. John immediately jumps out of his chair, and goes to open the nearby window. "Come over here," he orders. Sherlock obeys, all but running to the window. He clasps the windowsill hard until his knuckles turn white, and he's breathing raggedly. "Do you want some tea?" John asks because tea is the answer to everything. "No," Sherlock says, feeling a bit calmer already. About ten minutes later, he goes back to his position on the sofa as though nothing had happened. But, of course, something did happen and John knows now. But when he finally builds up the nerve to look at John, he doesn't see that look of pity that he thought would be there. Instead, there's a look of worry, and Sherlock, much to his own surprise, is okay with that because no one has cared about him in a long time that didn't have an ulterior motive or wasn't his Mum; it felt kind of nice, actually.