I am 16 years old, and I also started my period at the age of 12. I have about the same breast size as you. Breasts come in all shapes and sizes, so yes it is completely normal for them to be small! My mom has always had large breasts, and I've never gotten them. There is no such thing as a "normal" breast size. Everyone's are different, and I know from experience that having smaller ones isn't a great feeling, but you just have to try to OWN it. Also, you are only 14, so there is still a chance for them to get bigger, but if not just know that there is nothing medically wrong with having small breasts. I have no clue if there are any natural ways to make breasts grow, but if there aren't, don't stress! Small breasts are not a bad thing.