I don't understand why this would give someone anxiety attack - it would suck if the interviewer sat next to me and watched my every keystroke, it wasn't that in my case. He just set me up and left to do his job. I was on my own, until I finished and called him over to show the bugfix.

I have anxiety issues when an interviewer asks me some obscure syntax option for grep command or some b-tree stuff that I learned in college decade ago (and never used in real life).