Man, that sounds a whole hell of a lot like my high school experience.
Pre-everything me + hot girl I had a huge crush on that gave me weird signals = 'sorry, I'm just not that way'.
It's just one of those things, man. You move on.
I will say that, if you plan to start, HRT will change a lot. There are a ton of women out there who are looking for a good man, bits be ******.
IE: they're a lot less likely to reject you if they're looking for a man and you visually/mentally are one. As my slightly bi but more interested in men/masculinity fiancée says, "Penises are pretty unimpressive 95% of the time anyway". It's not a make or break for as many women as you may think.
I know it sucks being pre-everything and looking out at the world like you're stuck in limbo, but it gets better. If this girl isn't into you, it's no big deal. The world is filled with women. Just be confident, keep your eyes forward and stay focused.