This can *really screw with you if you've already got issues with anxiety. When you have an anxiety disorder, a low-level claxon is constantly ringing in your brain, no matter what you're doing, if you don't learn to tune it out you can't function like a normal person. When it does start to blare for real, you're genuinely unsure whether you're in trouble or not. You think to yourself, Maybe I'm over-reacting again for nothing, just like I do all day, every day, you don't get out in time.