Thaar, I am curious to see if you have discovered anything further with your sensation. I have been searching for some insight into the exact same feeling you have! I just could not come up with the words to even begin to google it until I ran across this message board.
I have not been able to work up the courage to push my body to hold the sensation more than a few seconds. You nailed it.. it feels as though I could lose control entirely if I continued. It’s a bizarre feeling that I’d love to know more about.