Still Doubting Everything

I need your help with my situation please. I started questioning my gender when I was around 8 or 9. I'd tuck my genitals so they'd "disappear" - in the bath, under my clothes. I prayed to God, to anything that would listen, to please let me wake up as a girl. I'd wear padded bras and it felt amazing to see that shape. Started wearing panties and stockings under my regular clothes. I remember comparing my body to adult women's bodies and just assuming mine would develop the same way. Spoiler: it didn't. Once I dressed up in my mother's clothes and knocked on our door. My father opened it, didn't recognize me at first, then got angry and told me to never do it again. That pretty much taught me to hide it. The teen years were a mess: Around 16, I found out about "transvestites" and thought okay, that's me, just a fetish. Because I'd get into this cycle - crossdress, feel right, get aroused, masturbate, then immediately after orgasm this wave of disgust would hit and I'd throw everything away. Rinse and repeat a hundred times. The thing is, when I was home alone, women's clothes were just my default. Not for sexual reasons, just because they felt right. But I didn't like what I saw in the mirror - I saw a man in a dress, not the woman. At 18 I learned the word "transgender" but back then without real internet, I thought it just meant permanent crossdressing. I had no idea about HRT and that it could actually change my body. I thought I'd just end up looking like a man with boobs.

My 20s and 30s were basically denial on repeat: I learned what HRT actually does, but by then I'd convinced myself I was just a fetishist, not "really" trans. The feelings would quiet down sometimes, but they always came back with vengeance.

Regarding famous "magic button" test - I'd press it without thinking and hesitation! And the gender envy... it was unreal. Every woman I liked, I didn't want to be with her, I wanted to BE her. I'd imagine myself in her place, with her body, her clothes, her life. Then there's sex! I mostly slept with women, but during sex I'd be imagining myself in their position. When I was younger, it wasn't too big issue, but now I have ED without physical cause. I've done blood test and everything seems fine, I just can't engage with male sexuality anymore even with cialis etcetera.

Then FaceApp happened: I used the gender filter and it opened my eyes! I saw myself as a woman and realized I could actually pass. Not just pass, but be attractive. That image has been living in my head rent free ever since, and the dysphoria that was always simmering in the background kicked into overdrive.

Other random things that might matter: I love video games but playing male characters feels disgusting. I can only play as female characters. If a game forces me to play male or has an unattractive female option, I just won't play it at all.

Here's the question:

Even with many years of evidence, I still have this voice saying "what if you're wrong?" I'm not 100% certain, and it's driving me crazy.

Logically I know that men don't spend decades thinking about this. If I was wrong, I'd have stopped wanting this by now. Early HRT changes are reversible if it feels wrong. But the doubt is still there!

For people who transitioned, especially those who started later in life: Did you have doubts like this? How did you know you were making the right choice? What did "rightness" actually feel like when you started HRT? I think I just need to hear from people who've been where I am now.

Despite ALL this evidence, I still have imposter syndrome meaning that I'd just pretend to be a woman. I'm not 100% certain and keep thinking "what if I'm wrong?"

For those who transitioned: Does this sound like being trans, or am I somehow missing something? Did you have doubts before starting HRT?