When are done developing?

I'm 16 years old and I've had my period since I was 12. I wear a 34C, but my left (and nipple) is significantly larger than my right. I'm so self conscious about them, and I know that I'm too young for surgery. I'm hoping that they will even out by the time I'm in my 20's, but I've read that are usually done growing about 3 or 4 years after you get your first period, even though I'm hoping that isn't true in my case. Please help! Are my s done growing, or will they even out in a few years? And are there any exercises I can do? I'm desperate! (I'm aware that uneven are common among teenagers. I'm just worried that my s are done growing and won't even out.)c