Lots of children go through the same as missrandom.
Our eldest daughter, a very pretty girl, was a tomboy. She used to be in the five-aside football team at school, etc. However, once she reached 14/15, all that changed & she went on to become a beautiful young lady, wearing feminine clothes (not tarty) & makeup.
She's now married (albeit just filed for divorce after 17 years) & has two beautiful little girls herself.
Our other daughter on the other hand, was always a girlie, girl & loved her dresses & dolls!