Breast

I'm very insecure about my size, I'm an 34A and well my right boob(if I can even call if s boob lol) is slightly bigger then my left. I know because in the shower I look down and put my fingers horizontally pointing at each other on both sides, and I notice that I have a small spacing, it's hard to explain but I can't tell that my right is bigger, is this normal? What does it mean?