Don't feel stupid!
Many of these rules make no sense.
Lots of rules change every year.
No one can get them all memorized unless they have little else to do in life., and you are a very busy student.
True. Especially last weekend I studied for 3 tests, though one of them I focused more on than the other 2....and it didn't work out exactly how I hope. I mean it wasn't a HORRIBLE grade, but it was in my opinion (I put standards on what's good or not...with exceptions to at least one subject (chemistry)).