First thing that comes to mind is that he *always* has an escape plan, no matter where he is or what he's doing. He never was like that before. He talks semi-often about things such as "if I had to, I could kill someone". He always has a knife on him, and a big one by his bed, he didn't have the *need* for that before. I can't come up behind him and hug him, he still jumps and turns around quickly in a really defensive (and scarey) manner, he certainly didn't do this before. He takes the longest and hottest showers of anyone I've ever known; guess he's still compensating for those 2 min's of cold water.
How could I forget: he *could NOT* fall asleep after he got out, not without dropping from exhaustion. His brain would race if he'd lay down. He'd wake up frequently, then not be able to go back to sleep, he'd have horrendous nightmares, reinforcing that he didn't want to go back to sleep. He's on medication for sleeping now and it's much better.
This is just some of the stuff I could think of quickly after reading your post. If I think of more, I'll post them later.