Hehe, I'm kind of the same way. I've been going, "Man, if I had answered this instead of that, I would have made a B instead of a C." But after doing some heavy thinking, I've still got a B in that class. One bad exam is not going to doom me (or it might : o ).
This exam in Foundations seems fairly easy. A lot of practical information and general 'must know' stuff. Good luck with studying everybody : )