Despite all but believing I was a boy until that horrible day I got my first period, and being about as masculine as a "girl" could be for the vast majority of my life, I never even had a clue I might be ftm until I was 18. Of course, I didn't even know what an ftm WAS until then (yes, I was sheltered). However, regardless of realizing I was ftm at 18, I waited another five years to even look into transition, and a year past that to start. I tried identifying as lesbian for a year or two, but it didn't work for me at all. But you can count me among those clueless folks who took awhile to clue into the trans bit.
As per masturbation, I NEVER did it prior to transition. Part of it was my upbringing, part was my repulsion at my particular genitalia. Once on T, however, it was impossible to avoid. I think, had I not learned to overcome my negative feelings concerning masturbation, I would've ended up in an asylum from the excess sexual frustration. Inevitably, what I realized was that I would never have the penis I wanted, so I might as well learn how to be happy with what I have. It worked. Now the only genital "dysphoria" I have concerns thoughts of having sex with other people.
SD