I've been there before--- if I get toooo stressed out I risk a panic attack or meltdown, so if I know I'm stressing out, I'll try and find a bathroom to just sit and cool off for a moment, to gather my thoughts. I am bad at stressful stuff. One of my last jobs, I couldn't get away or anything--- not even to a bathroom--- I had a panic attack, slammed my head into a desk and I couldn't go back there after that. Not very ladylike, I know. I try now to allow myself time--- time to do my work in a timely manner and time to keep a good pace without stressing myself out too badly. I also make sure I know where the bathrooms are.