You really are exactly what you really are. Whether that's cis, or trans, or NB, or a secret fourth thing, those are all just labels. The label doesn't matter. What does matter is whether you feel that you're doing the right thing for you. Everything, and I mean everything, is all made up in our heads. You are a brain inside a dark jar piloting a meaty skeleton on a spinning rock whipping through space. Even our direct sensory input is all mediated by the brain. Therefore, nothing is true, in a really empirical sense, in a way we're capable of measuring. Everything is all made up by the brain.

And if nothing is true, then everything is permitted. You do you, in the way that feels right to you, and don't you let anyone stop you. This is about your personal truths, which are as true to you as anything can be to anyone. If you think you really are trans then you are. If you think you aren't then you don't have to be. There is no objective measure of truth here.