Here's the thing though - you don't really have that kind of control over your gender identity. You can't really control whether you want to be a male or a female - it's innate. Kind of like you are comfortable with your identity as a male right? You wouldn't want to just become a woman for the heck of it.
Nobody does. Ever.
If a person is born female, either they will be comfortable with that gender their whole lives or they were never comfortable with it. Some people transition to the gender they relate to early in life and some people take longer or never transition at all, but the point is that you can't really control your gender identity.