My apologies if this has been covered recently - I wasn't able to find it if it was.
When I was about 8 years of age, I apparently experienced a number of intense prostate-only orgasms through direct pressure on my perineum. I lived on a farm when I was a child, and I would often play in our barn. One day I was climbing a knotted rope, pulling myself up from knot to knot and sitting on them while resting my arms momentarily. I discovered that by resting on the knots and squeezing my legs together, I would feel a pleasurable sensation; I repeated this series of motions and eventually had an intense orgasm in what I now am certain was my prostate. There was no sexual arousal on my part, no fantasizing, no erection, and during orgasm, no ejaculatory spasms or ejaculate. I was also able to have these orgasms by slowly pulling myself up pipes like those that support swing sets on playgrounds.
I don't remember how long I masturbated this way, but I don't think it was very long. Roughly six years later I had my first "complete" orgasm with extreme pleasure in both my prostate and erect penis, as well as a powerful ejaculation. This was with erotic fantasy.
I've found very nebulous references to infants/children masturbating on the Internet, but never something like what I experienced. I'm wondering if anybody here has had similar experiences as a child, i. e. intense prostate orgasm with perineum stimulation? For medical professionals here, is this common or rather unusual? By the way, I never tried prostate stimulation via my rectum at that time, but I assume it would have led to a similar response. As an 8 year old, it never occurred to me as I had no understanding of the biology of the situation.