Pain in breast during periods

Hi, I am 25 year old. I got my periods first when I was 14 year old. I always get hell lot of pain in my breasts, 1 week prior to my periods. The pain is so high sometimes that i can't sleep in any posture, i cant walk fast, don't even think about jogging or running. But the day i will get my periods, everything goes fine without any pain. Sometimes i feel my breasts size is a bit big than normal. My height is 5'7", weight 62 and my bra size is 34D. Moreover, my breasts are not symmetrical. One is quite big that seems to bulge out from my bra all the time :(. I need to know the reason for all the weird things.