I need birth control!! Help!

For the past 2 years my period has gotten bad. Almost 10 days long, irregular, extremely heavy (going through 2 or more super plus tampons every hour), and the worst cramp. I get cramp in my back, stomach, and legs. And they are so painful. I didn't go to school today because I knew I couldn't even stand up out of bed without falling to the ground. I've talked to my aunt before (I live with my dad and brother full time, aunt is only female adult in my life). I've asked her to put me on birth control before and I explained my period and insured her I don't have any interest in having sex. But I need birth control. I can't stand my periods and being in so much pain. Also even though I'm not getting the birth control for sex, I have had sex before and It would be nice to have a little more protection if I were to have sex again. Do you guys know any way I could get birth control without a parent / adult ?