A wide range of emotions rushed through him, but the most dominant was anger. The rush from the struggle with Tom and the blow on that filthy little bag of libs still pumped through his veins.
The image of John, skimming his hands down the inner thighs of that idiot appeared for his eyes. It made Sherlock's blood boil. Yes, he had asked them to distract potential intruders. The sane part of his brain murmured that he couldn't blame John for that, but that part was very far out of reach.
Plus: Who was the flirting expert here? John had known Sherlock was not interested in flirting, unless very necessary, like this case. But he wasn't the one who had a history of dragging on dates and dumping them (sane part: but John dumped them because of him. But again: this was not heard).
Sherlock's ears were ringing of the blood pumping and his heart throbbing of rage. The last time he had felt like this was when Mrs Hudson had been assaulted in 221B. And that ended in an American falling on bins countless of times
Of course he was planning on hurting John, he would never do that intentionally. But still that uncontrollable fit of primal hatred was rearranging his mind into chaos.
When John came back, Sherlock didn't dare to look at him or to talk to him, in fear he might burst and do something he would regret later. He hailed a cab, which took them home. When they were inside, Sherlock angrily threw his coat on the nearest armchair before John slammed him against the wall. It was hot and sexy, but they both were angry and furious and frustrated. Sherlock felt like he would burst at any moment and didn't hold back at length. During the cab ride he had tried to formulate sentences that sounded coherent, but all his plans fell apart when he began speaking.
"Do you actually know how hard it has gotten for me to separate emotions and and work!?" Sherlock shouted frustrated and angry. "Keeping an emotional detachment became very difficult when you showed off your military dogtags and trousers and boots and attitude! I have never been so sexually frustrated ever before!! Do you know how tormenting it is to think about you, watch you, but not actually touch you for the sake of emotional detachment or the case!? Many times I have thought: Fuck this case, I'm going to have John right now! but I couldn't. I was stuck with that maniac that wasn't even near handsome or interesting! And when I saw you dancing with that idiot and he, trying to kiss you- I... I-"
By this time Sherlock's voice was at it's breaking point. He had thrown so much emotion in and he shouted so passionately that he was getting hoarse, which got in handy because he was not exactly sure what he was going to say next.
((So, it was sexual frustration after all. I hope you can work with it!))