How do i get birth controll without my parents having to go with me?

Ive had sex 3 times this week, once no condom but he pulled out and non got on me, second time condom and he didn't ejaculate, third no condom but pulled out in time. Im tired of being scared that im pregnant. Im under 17 so i cant get birth control without a prescription...how do i get it without my parents knowing?