The talk/birth control/pmdd

I’m 15, I suffer from PMDD and take Prozac. I also think I’m ready for “it.” I’m talking to a boy currently who is on the same page experience wise. Has done about everything other than sex. And I absolutely am not going to just give it up to anybody, I plan on waiting a WHILE into the relationship to even bring up the idea, that’s just how I personally feel. Most of my friends are a lot more experienced with this thing and offer me a lot of advice however I’m not sure how to approach it with my parents, my boyfriend or my doctor. I really think birth control would be killing two birds with one stone, my pmdd symptoms and whenever I do decide on having sex. Currently I know I’m not losing my virginity anytime soon so I don’t know how to bring up to my parents that I’d like to get on birth control without them thinking I’m having sex. I know this is a big mess but I just need some advice. Will my parents assume I’m having sex? Is 15 too young? Is it worth any back lash?