What Mystique said - exam time is a stressful period, during which dealing with problems other than the exams themselves can be contra-productive in more ways than one.
Put on your best Horatio Cane glasses and write the hell out of those exams!
why else would she be ignoring me if she werent mad at me?
There's a myriad of reasons and the first (and worst) mistake you can make is to come to a conclusion based on conjectures. I could write, from the top of my head, 5 reasons why she could be ignoring you (or, rather, not answering messages, which need not be the same thing) that have nothing to do with being mad.
This situation, like most, requires inquiry. Ask her if everything's okay, express your concerns. "All we need to do is make sure we keep talking." (Stephen Hawking)
But right now, exams - you need to have a clear head to make sense of the complex hues of human social interaction :]