Breasts Aren't Growing for 2 years! Is that a sign of breast cancer or some other medical problem?

So im a teen and since 2 years ago my breasts haven't grown (im 15 and they haven't grown since i was 13) im worried if i have breast cancer or a medical problem. Also, is it normal to not have any kind of sensation when you touch your nipples? Because i dont feel any kind of pleasure or anything.