birth control

so my mom thinks birth control is bad and like can mess with your hormones too much and if you take it for too long you can't get pregnant and we were talking about birth control and when she went on it and i was sorta hinting to the fact that i wanted to go on it bc is 17 and don't want to have kids any time soon but my boyfriend and i have sex quite a bit and i just get scared that something's gunna happen bc sometimes he just pulls out and my mom asked if i wanted to go on it but i chickened out and said no way too fast but i do wanna go on it and idk how to bring it up. i feel like my mom knows that i've had sex with my bf but idk. i feel like she'd be happier if i told her i want to go on it just so i can't get pregnant but i feel like she'll like almost like be too protective if she knows i'm having sex. idk what to do..