birth control pills

Hey ladies . So my period is irregular and I have 50 days of cycles . I never took birth control pills before . So I was wondering if they can help with my periods to come early or for my cramps ? Has anyone tried it before ? Or people just use it for after they have sex . My period hasn't been on the  schedule lately and I took a pregrent test it was negative . But my period hasn't come yet . So I'm going to use this method and see for my period if not. I will go to the doctor .