Seriously...make up an excuse and just show up.
Also find out which classes take attendance and which don't. The ones that don't, you don't really have to explain anything (those are usually the ones that only have 4-5 tests per semester, and no other grades), so just show up and take the tests.
But I suggest talking to your professors, make up some BS reason why you weren't there, and throw yourself at their mercy. But, MAKE SURE YOU DO IT IN PERSON. No email, no phone call. People are much less likely to reject your request, much less likely to be sympathetic, if they don't have to turn you down to your face.