Advice ladies?

So I'm 15 years old and I suffer with extremely bad period cramps for the first three days of my period. The pain is excruciating and I struggle to find a method to get rid of the pain. I've spoken to my mum about seeing a doctor to see if they can help but I can tell she doesn't want me to go in case they put me on the pill and I go having sex with my boyfriend which she wouldn't like. I don't plan on doing that anytime soon but there seems to be no persuading her! Any advice? Should I see someone on my own if she continues to not allow me?