girlparts=girl is a REALLY hard lesson to unlearn. What I've found helpful is really tuning into that inner boy, having a conversation, having a good hard look at who that person is. There are discrepancies. Some are more obvious than others. Some are also more achievable than others (Sorry J, you will NEVER be 5'9 unless I buy a medieval rack and risk paralysing injuries) - but undeniably there is a boy in there. In a way I always knew there was. I just "knew" that I was a girl with a boy-brain, in a weirdly dissociated sort of way, rather than the more common narrative where kids "know" they are (in a parallel situation) a boy in a girl-body. It takes a certain level of ego to make that switch, to making the mind you know works one way the dominant force in your identity, rather than the "objective fact" you were taught when you could barely speak that gender labels are applied based on parts. Trading solid, "infallible" (nope) "fact" (eehhh) for something so subjective as trusting your own mind not to be playing tricks on you is HARD.
As for being normal.
Every single human being who ever lived has experienced this life differently. They had their own emotional profile, their own identity, relationships, aspirations, hobbies and desires. Take any combination of factors and someone, somewhere in history has probably lived it. Statistics are weird like that - there's 365 days in a year and yet in a class of 30 there's better than even odds 2 will share a birthday. (I was one of that pair in my class at school). Thing is Normal doesn't exist. EVERYONE has something that makes them different. It doesn't seem fair, at all, that for us it's not belonging in our bodies when the kid next door got a minor allergy to broccoli and your cousin has an unhealthy obsession with collecting dryer lint. But it's hard to embrace food sensitivities or obscure collections as identity traits. Embracing who you know yourself to be... even just knowing yourself in the first place... that's more than a lot of people ever even go looking for. It isn't easy. If it were EASY, more people would probably do it, even out of curiosity. But it's not.
As a nerdy side note that may be either really deep or really stupid depending on your point of view... in Mathematics, the normal as seen from any given point on a curve is literally going off in a completely different direction to where the curve is going. Normal is specific and different for every point. I can't help but think that sort of applies to people too.
