Boob advice.

So I'm 18 soon to be19 and i started my first period when I was eleven .. all I had for PMS symptoms were just the regular cramps,mood swings and backaches... two months ago I started having a new PMS symptom(is that possible?) I've been having really bad pain on my boobs and they've been very tender,swollen and constantly hurt around and on the nipples. I'm not sure if its because I'm constantly sexually active or if this is normal. I wear sports bras 24/7 and sometimes the pain gets so bad I can't even wear a sports bra...is this normal or should I be worried.? ADVICE PLEASE 😭