First time prostate orgasm?

Beginner/intermediate user here, I (25M) have been using a helix syn on and off for a few years now. I have a progasm as well, but that one actually hurt for me so the helix has been my go-to. I ordered a progasm jr today and am excited to give that one a whirl.

I had my first session in a couple weeks just the other night and it was the best one I’ve ever had. I find that my best sessions are spur of the moment when I’m already super turned on and involve little to no prep. I already had every intention of masturbating normally that night, but decided last second that I wanted something more. So I lubed myself up, lubed the helix up, popped it in and went to town.

It didn’t take long for me to start having involuntary contractions and to feel those familiar p-waves, which just felt like a mild sense of warmth around my pelvis and stomach for about 10-20 seconds at a time. As I began to focus on the sensations I was feeling, the involuntaries grew more violent. I didn’t fight it. I surrendered to it, and welcomed all of the blissful sensations that my body was feeling, from the violent, hip-bucking, bed-shaking contractions to the moments of complete stillness.

It was during one of those moments of stillness, maybe 25 minutes into my session, that a new sensation began to hit me. There was pressure building up in the head of my penis (which has been rock hard this whole time FYI) and radiated down to my pelvis, where it became a warm euphoria far more intense than any p-wave I had ever experienced. It began to ripple outward, down my legs, up my torso and into my head and face. I envisioned my penis as a radio tower of sorts, transmitting this blissful sensation around my entire body. I couldn’t move; I laid still, flat on my bed, focusing intently on the feeling in my pelvis, as well as controlling my breathing. This continued for about 5 minutes, and by the end of it I barely felt human. I felt as though I had melted into my bed. My body didn’t even register that it had an object inside of it. After a few more minutes of relative inactivity, I really had to pee, so I removed the helix and called it a session. Could I have held out and continued? Maybe, but the urge to pee sensation was beginning to get uncomfortable.

My question is how does one know when they’ve had their first prostate orgasm? Are there specific signs to look for, or is it one of those cases where “if you have to ask if you had one, then you did”? Either way, it was a truly unforgettable session, and I feel like I’ve taken a big leap forward in my anal play journey.