Boob question! GIRLS ONLY!!!?

Okay, so I'm 12, almost 13, I've got boobs, armpit hair, hair "down there" and discharge(Lots more recently), no period yet. My problem is that my boobs are growing, and my right one is bigger than my left one. I know they say it will grow unevenly, but the just keep growing at the same speed, and the left one is always a bit behind. I'm not looking for boob enhancers, just wondering if there is anything that can make the left one catch up?