What should I do?...

Hello, I am a 16 year old girl and I need help. I am having sex with my boyfriend, and I want to tell my mom that I want to have birth control pills so that I can make sure that no accidents happen while we are using a condom during sex. But i feel like I can not tell my mother that I would like to have birth control pills, because of the way she is. It’s very hard to tell my mother things that I want/need to tell her. And my parents have an idea that I am sexually attractive (which is true) but I haven’t told them because I’m afraid that they won’t trust me, and they would take away my boyfriend from me because I am sexually activate. What can I do to over come this fear? Or is their anyone that can give me advice?