Very close to super-o

I have been using Aneros for about a year and recently I figured the way to reach to a certain point where my heart starts bumping like crazy, I am starting to shake and I am totally losing my mind. However, this lasts only a few seconds and I can do something to prolong it. I can feel that I am one step just before getting a real super-o but it's hard to find out what I should do to pass to the other side.

The way I am doing it is to hold a contraction maybe 50% of what I can do for 5-10 minutes and then this happens. Those minutes I am pressing a certain point with Aneros which I figured out to be the best for me. I am always using it in a hot tub which feels awesome. When I get to that point I am stopping the contraction and trying to relax and enjoy the whole experience.

Any tips / advice that could help me would be highly appreciated.

Also some feedback so far:

1. The next day after having a session I feel so full of energy. Does this happen to everyone? Any explanation?
2. I cannot have any results after using Aneros for more than an hour. I usually get to the top within the first 30 minutes or less.

Thanks for everything,
Alex