Kaylee, I think the whole 'secret' is listen to yourself, not what others around you say or what you think they might be saying. And yes, when you start to doubt, focus on all those feelings you have that cannot be explained any other way.
As to feeling worn out and not natural, maybe you're trying too hard. I'm understanding more and more that I don't know exactly how I'll be a woman. I just know that I am. And so now I focus on being ME rather than being a woman. Well, I KNOW I'm a woman and so what's the difference? When I only try to be me, I do feel natural; I feel right and can express my gender in ways that feel comfortable. If I try too hard to be a 'woman', then I find myself acting a role - someone I might imagine myself to be in the future. Don't force it. Be who you are right now. Allow that much.
In my third session of therapy I decided to stop trying to please others and go with what I know. I told her that I AM transgender and don't need her to make that decision for me. I need her to support me as I continue. While I hadn't yet told her firmly that I know I'm female and pretty much binary, I told her about a new girlfriend who told me "The beard HAS to go!" The therapist jumped to say watch out for what other TG's tell you - don't jump to please them either! Maybe you're not binary. Maybe breasts and a beard is who you are. My point there is again, let yourself be YOU. Stop acting and let yourself feel natural - ALL of you. Don't try to suppress feelings that are there but don't try to create feelings that are not there now.
Sorry to ramble. I'm not the best one to be saying all this as I'm still working on getting it straight myself! I just feel for you and pray that you can find yourself. I'm confident you can.