rant?

I really don't know where to start. I don't know if this is a question or a statement to be honest. Let me start off by telling you I'm a junior in high school... I'm 16 years old. My boyfriend is a junior as well and he is turning 18 in August. We have been together since I was 13, a little 8th grader. Both of our parents are well aware of it. We haven't separated or taken breaks... we have always been a couple. We have been through some rough spots, but that's normal for a 3 years relationship. Anyways... long story short, we have sex. What couple in our situation wouldn't? It's so obvious that we would. I don't understand why my parents refuse to let me on birth control. I've never asked but they always are strongly against it. They will not even take me to a lady doctor... I'm almost 100% sure my periods are not normal and I cannot even visit a lady doctor because my mom accuses me of wanting to be on birth control. I have unbelievable horrible cramps and huge clots. Sorry tmi. You get the point... 
our only form of protection is condoms and it's a hassle getting them without people finding out. I just don't know how to talk to my mom or anyone about this. We have been together for so long and it's very frustrating for us. I need advice or just someone to talk to. Ladies only please 🙁💓