When I had just turned 13, I discovered how to masturbate. My penis was about four inches long and I was developing a nice little bush. I had no underarm or facial hair though.
One night I was up late watching t.v., and I had an erection for some reason. I was in pj bottoms and no shirt. I never wore underwear with pjs because it was comfortable. I shifted once and my penis rubbed against the bed and I realized that it felt kind of good. So I repeated the process again and again and every time It felt better and better. I did this until I felt that I had to pee. So I got out of bed and went to the bathroom and tried to pee but I just could not. Then I went back to my room and continued to hump my bed until I felt like I had to pee again but I still went on.
I felt this really good feeling in my body. I was a little scared but still surprised. I turned the light on in my room to see a dark spot on my pjs about the size of a ping pong ball. It took me two months actually to realize that I could just use my hand instead of humping the bed.
I have masturbated most everyday since that day.