Given that Damian's throat was probably the worst burnt part of him, when Brown started strangling him halfway-to-death the first thought in his head was the bizarre, absurdly glad notion that at least his windpipe was too constricted for either of the two women to tell how much he was screaming from the pain. It would be bad enough for her to kill him while he was lying weakened in a hospital bed, but Damian would never forgive himself if he died screaming and crying like some pathetic child, even involuntarily.
 
The second thought that popped into his head around the moment he realized he couldn't get her hands off of his throat was that [i]she could actually kill him right now.[/i] This mainly resulted in a lot of kicking and useless, irrational struggling but from little bubble of shock-induced detachment the rest of him was inhabiting he was extremely surprised. It wasn't potentially being killed. The League had raised him in a long tradition of rewarding failure with death even if he was always above it, he practically tempted Drake to try it every day and even Cassandra as he knew her would have killed him for a big enough failure if she were allowed.  But from Brown it was almost completely unexpected. The last half of that thought combined with the lecture drove one thing home:
 
[i]You almost got both of us killed.[/i]
 
For once, something was actually undeniably [b]his[/b] fault. Not being choked, he wasn't insane. But as far as the explosion, his injuries and the failure of the mission went there was too little room in the sequence of the day's events for Damian to shift blame or minimize what had happened. He had opened a door when every instinct he had [b]knew[/b] it was a trap, due to stubborn recklessness. Both of them had almost died because of it and even though making a game out of taunting Brown was one of the few things he generally felt completely safe doing, she was now mad enough to kill him.
 
Guilt was a fairly new feeling for Damian. Genuine remorse was even newer.  
 
So after Stephanie Brown said she really [b]would[/b] kill him if he ever did anything like that again and let him go, he actually listened and shut his mouth. He had too much to process anyways. Instead he very carefully kept his face and body blank enough to potentially fool Cassandra if he had to and waited until Kane and Brown both left. He looked around then closed his eyes and counted their steps until he was absolutely sure there was no one anywhere near him.

He was Damian Wayne, Son of Batman. He had never cried and never would.

No one would ever see otherwise.