I love this site and wanted to contribute my own story of my first orgasm.
It was ages ago. One night, after I was tucked into bed, I found myself fondling my penis. I had played with my dick before, and liked making it get hard. But this night I discovered a particular spot, a little below the glans, on the underside (well, actually on top, lying on my back with my erection pointing up toward my head). There was an extra little 'nub' of loose skin there, and it just felt really good to roll it around. I did this for 10 minutes or so, enjoying the small waves of pleasure that produced, and soon fell asleep.
My family lived in a big old Victorian house, with a winding staircase in the front foyer that went upstairs. Under the stairs was a closet w/ a curtain instead of a door. Behind the jackets, etc. that were hanging in there was a pile of cushions. I think we had gotten new cushions for one of the couches and this is where the old ones were temporarily piled up. I used to like crawling in there and curling up on the cushions, enjoying feeling safe and hidden from my family but still being able to hear what was going on in the house.
Well, this time in the foyer closet I remembered my discovery from the night before, and soon had my penis out and was rolling that little nub of skin around. I found it worked best to make little circles with the index and middle finger of my right hand. Soon I was feeling those wonderful waves of pleasure again. Instead of stopping or falling asleep, I kept at it. It felt so good! The pleasure reached a crescendo, and I think I blacked out briefly. I found myself fallen back on my elbows, gasping for air and shaking, and my dick was rhythmically contracting. I wasn't sure what I had done, and felt somewhat guilty about it. But that didn't stop me from doing it at least once a day from then on!
I finally knew for sure that I was 'normal' and that what I was having were orgasms (which I had read about in my parents' copy of 'The Encyclopedia of Sex'). For years I masturbated in this same way, though at some point I switched to holding my penis in an encircling grip and moving the skin of the whole shaft up and down, instead of just that most sensitive little nub. I found I didn't get as sore that way!