I either freeze up and can't say anything.. Or I go crazy... Yelling back, arguing, I've been in more than one scuffle.. I think it depends on if I think I can take the person yelling or not--or if I'm simply too angry to care.
When I freeze up.. I think.. I think it is out of not wanting to regret doing something. I freeze up, like it is my intial "Holy shit, don't flip out and get fired over this. Think about it."