Feeling different from your friends for any reason can be hard. However, your breasts are likely to continue to develop during the next couple of years. Heredity (the genes you inherited from your mom and dad) is the most important factor in determining how big your breasts will be. No creams, special exercises, or clothing will permanently change your breast size. Your breasts may change with weight loss or gain or after a pregnancy, but for the most part the size of your breasts stays the same once you’ve finished puberty. Hang in there and ask your primary care provider about any concerns you have at your next check-up. In the meantime, you may want to try a bra with extra padding.