Is the "wrongness" that you feel with presenting as male purely an expression/conformity thing? If you could dress and express yourself as feminine as you feel on the inside, would that be enough? If so, then you might be a non-conforming guy. GNC people, whilst not trans, do have a fair bit in common with trans people in terms of existing in a society that has a largely close-minded understanding of gender.
Otherwise, does it bother you to be referred to using masc terms (like "son", "brother", "father" etc.)? Are there parts of your body that cause you distress, because they don't line with what you expect or think feels right? If yes, then you may benefit from experimenting with labels under the trans umbrella. Only you will be able to determine if it feels right, but without trying you may never know.
I am not a trans woman but I was hoping I could chip in with a bit about Finasteride as I used to be on it.
Finasteride is not a general anti androgen, but it does block DHT, which is what some T gets converted to and is the most potent/effective form of T. I'm a guy and I was briefly on it for hair loss but I stopped because it made me depressed (dysphoria) and I also felt a little weaker. So at least from my experience, I would call it an anti-androgen, even if it works specifically against DHT.
One side effect of finasteride reported by some men taking it is breast development, so I would be very surprised if it has anything to do with what you are noticing with your chest.
Have you had a blood test recently? If that's all good, breast growth can take a long time (several years), and ofc the full extent of it varies from person to person.