birth control

So I've had heavy periods and terrible cramps since I started my period. I've tried convincing my mother to let me use birth control but she got angry and said "Hell no! Unless your having sex, and I pray to god that you're not! You have no need to be on birth control!"  I don't know what to do. I do volleyball and believe me, it's super embarrassing when you bleed through a pad during the middle of a serve!  She still said no after what happened and blames it on me! She said that it's my fault for having a heavy period. How do I convince her to let me use birth control? What's the best form of birth control?