1. I knew something was wrong when I had a pregnancy scare at 20 and endured a days-long emotional breakdown punctuated by several panic attacks. I knew if I was pregnant, I could abort and have my family's full support, so my reaction confused me. I spent some time trying to figure out why the idea of being pregnant made me want to die, and discovered a term that seemed to describe what I'd been feeling: dysphoria. 3 years later I experimented with some non-binary identities, but that didn't work out. I had a hysterectomy, felt a lot better, and went back to thinking I was mostly cis. But it's reared its head again now at 29 and I think I may be FtM.
2. Looking back, most of us have memories that seem so OBVIOUS in retrospect, but not all of us do. Growing up I thought I was a girl and would get mad when adults thought I was a boy. And yet... when I was 5 I tried shaving my face. (Yes, a 5yo getting hold of a shaving razor will end badly.) I always wanted to be able to stand up to pee. I made bets with my grandmother that I'd grow up to be 6 feet tall. As a teenager, I played around with taping my boobs down with packing tape when I was alone in my room, "for lulz". But I never thought I wanted a penis, a beard, never thought I wanted to be seen as a man. Not until a month ago.
3. When I was 24 I came out as 'agender' to my mother and my best friends. My husband (I was married at 22 right out of college) was well aware of my questioning the whole time so I didn't really need to 'come out' to him aside from the initial "I think something weird is going on with my gender". Reception was good; and there was honestly a lot less fanfare than I was expecting... or even hoping for lol. My mother promptly forgot about it all and still treats me exactly the same as before. At this point its likely that I'll come out as a transman at some point, though I don't want to do it until I have access to hormones and can show that I'm serious about passing in public.
It's important to understand that there's no right or wrong way to be trans. All any of it is is gut feelings and the choices we make about them. Sometimes dressing up as our felt gender is enough. Sometimes we want surgery and hormones. Sometimes we only want one and not the other. Sometimes we have complicated feelings on new names and pronouns. Sometimes it's cut and dry. Sometimes we realize that the changes are taking us in directions we don't want to go and we take breaks. Sometimes taking breaks makes us realize how badly we need it. Sometimes it makes us realize that we didn't need to go all the way after all.
The only thing that matters is this: how do you want to live and what is going to make you happy? A therapist won't tell you that you're X, Y, Z. They'll guide your thoughts, help you look over your life, help you see patterns and desires. They're very, very helpful for those of us who aren't sure. But they won't tell you what gender you are. Only you can decide that for sure.