Birth Control

So I want to get on birth control strictly because I play softball pretty much year around, for high school and competitive, and on both teams I have solid white pants. So it would be really nice for my period to be more regulated than it is. My problem is my parents think I want it because I've been with my boyfriend for almost 4 years now and they think I want it so we can have sex. I've told them and told them that's not in anyway going to happen, but they won't listen to me. With me only being 16 can I get it without my parents finding out?