I wanted to be a boy. I'm not a pshrink, so I won't attempt a diagnosis. I've talked to a lot of transsexuals, though, and first recognition of gender-body mismatch typically does occur at around age 5 or 6. So from my perspective, this sounds normal. For those who are reading along, gender is between the ears.
Sex is between the legs.
There's a difference, and there is no natural law that says they have to match. Girl's clothing was always a misery for me. It didn't belong on me. It was dressing up as something I wasn't. None of these questions can be answered without reference to gender.