Is there any way to predict . . .?

How big my will get? I'm 16 and pretty flat chested. I'm a 28A. Very very flat. I only started my period a year ago, so I think I'm just a late bloomer. My mom has size C. But I was just wondering if there was a way other than heredity to predict how big they will get? I don't want huge , its just hard being in high school and not having anything. I mean, they are definitely growing, but not fast enough. Thanks so much!