Telling the parents?

So I'm 17 and me and my boyfriend have sex. We use condoms but I'm so scared that something will happen and I will end up pregnant... But I don't want to tell my parents that we're having sex because they're super protective of me.. Like my mom freaked out for me asking her to buy me a thong.. She said she was "uncomfortable" doing it.... So I can't just TELL them.. But at the same time I want to get on the pill so I don't get pregnant...