I really do not know of a time I can recall of not having interests in men.
I dated and had sex with girls as a young man but some of the strongest orgasms I had given myself was when fantasizing about having sex with men but never really acted on it until I was about nineteen years old.
I came of age in the late 70's to early 80's. In the town I come from we had two adult theaters, one I call the "straight" theater that showed mainstream adult porn and on the other side of town where there was a decent homosexual population there was a gay adult theater.
When we turned eighteen, myself and three friends had visited the mainstream adult theater, I guess just for the experience I would say, it was kind of seedy, can't remember the name of the flick but we watched the movie and left, as we were leaving in the parking lot I couldn't help but notice the raging hard cocks my friends had in their pants, I tried not to stare but the urge to touch them was so powerful.
After getting home that night, while in bed, I fantasized about each of them jacking off to the movie we had seen giving myself a good powerful orgasm.
I had visited the theater a few more times on my own and just payed attention to the atmosphere which was a lot of older gentlemen there, most masturbating to the movie, some had coats covering their laps, some just masturbated openly and didn't mind being watched.
One time before leaving the theater I had to use the restroom. Trying to pee with half a hard-on posed an issue so I have to kind of lean up against the wall by the urinal, one hand on the wall the other pushing my dick down to pee, just as I finished up I happened to turn around and there was an older gentleman jacking off as he watched me pee.
He walked over and looked over my shoulders and whispered and said "nice cock", he reached around and started jacking me off, just the feeling of this guy jacking my dick got me raging hard it wasn't long before I was shooting gobs of cum into the urinal, this excited him too and as soon as I finished he shot his load right after me.
We both just smiled at each other and left the restroom.
For weeks I was giving myself orgasms playing out that scene in the restroom over and over again, I needed something more, what if I had gotten on my knees in that restroom and sucked that guys hard cock, would he have let me? would I have even done it right? I had never sucked dick before but I so wanted to, badly.
Some weeks later I decided to take a drive across town to the gay theater, my first time there I just sat out in the parking lot watching the stream of guys going in and out. I couldn't work up the nerve to actually go in.