Your English is fine! I hope mine is easy to understand. Let me know if not.
I identify as a transgender man, FTM, though I do still have times where I wonder, what if I am bigender or otherwise don't fit into the labels of man and woman? It's gotten easier throughout the years, after some experimenting. However, I was very back and forth about it, more so than you have been.
I've noticed that many trans people go through this, though some may not want to admit it. Confusion is okay. I've seen many trans people say that they had these back and forth feelings before transitioning, and once they did, it became easier to figure out specific labels. Their minds became clearer, whether they discovered they were indeed just transgender or actually bigender/otherwise did not fit into the binary of man or woman.
My confusion was at its worst when I was not talking about it, and felt like I HAD to choose one or the other, and fast.
If you're able to, try to talk to other people online about this. I'm not sure if you have any transgender friends in real life. I would really advise that you try to find another therapist who specializes in gender who can help. Is there a LGBT center nearby, with trans care? Try to get as much talk therapy as you can, that way you are prepared mentally for anything you discover about yourself.
If you go online, talking with other transgender people might be nice, because they can give you their experiences, as well as refer to you as female for a period of time if you want to experiment.
Good luck on figuring yourself out!