What the hell is going on? full body shaking and ejaculating without aneros?

I am a 24 straight guy. Aneros enables me to know my body and enjoy the extra happy things. I found something interesting after i used aneros for 6 months. Yesterday I didn't have any schedule to do aneros session. I laid down on the couch and watched drama. I bent the knee and feet on the couch. Suddenly, I felt my leg shook a bit involuntarily. It's like exactly the same when you have your aneros inside ur body and "do-nothing". When I stretch the body, i felt a pleasurable feeling. I have no idea what's going on. I went to the bedroom and laid down, did nothing, thinking hot girls. I feel like you actually could control your body. After a minute or so, I have intense full body shaking, hard erection and the heart rate got faster and faster. This lasted couple mintues. And i ddin't want that stop. feel great. I flex the whole body and coudn't hold back anymore and I had a traditional penis orgasm. WOW..It is a unexpected session. feel great..but..I still have no idea what was happening.