Interviews are rarely supposed to be anything but tense. Hell - the "draw a pig" one was ridiculously tense. Is my pig too big? Too small? Not enough tail curl? Should I define a gender? Is my dragon burning down the barn behind it appropriate?
Right, but the tension increases exponentially when you NEED the job. Well, at least for me, because I'm such a loyal employee I only ever interview when I DON'T have a job (like is currently the case).