Help with bra fitting and sizes?!?

Ok so my boobs are just starting to grow and I wear a 32 A. Recently my bra has been slipping up. I try loosening the straps and every thing!! But it doesn't work! I also measured my boobs and it said I was a C cup. WTF? I don't have a lot of boobs.! Plus I don't really want to go get measured in fear my boobs are too small to be measured! Please help!!!!!!!! D: