Fluttering....Involuntaries?

I'm a hard gainer, had lots of good feelings but never a Super-O

I was recently using my modified Helix.

I was on my stomach which is my best position. Lately I just relax and breathe deeply and steadily focusing on my stomach expanding and contracting. As time goes by it seems like my stomach "drops" or "hangs" more as I relax. As this happens I try to focus on letting my stomach or pelvis " hang" lower into the bed. In this session I found that upon exhale, I would feel my stomach relax and slowly settle downwards. If I REALLY tried to relax and tried real hard I would get another tenth of a percent relaxation at which point it felt like the Helix started to "flutter". That's the best word I can describe. The fluttering was brief, maybe 2-3 seconds, very soft and mild, and would produce a mild form of pleasure but nothing crazy. I continued trying to replicate this fluttering at the very bottom of each exhale. Sometimes it was very hard as I wasn't able to relax that tiny last percent to allow for the fluttering to happen. Eventually I got into a rhythm where I would exhale, the Helix would flutter for a few seconds, then I would repeat the process again. Deep inhale, deep exhale, and maybe some fluttering. I would say I was getting a flutter 50-70% of the time. It almost feels like whatever muscle that causes the flutter is so weak that it can only cause the movement if everything is COMPLETELY relaxed.

The challenge is reaching that level of relaxation but moreso to be able to hold the exhale. I almost feel that if I didn't have to breathe, I could just let my stomach settle and the fluttering would continue. Eventually the fluttering was causing some pleasure to build. It was building VERY VERY slowly. It felt good and I could imagine it building into something unebelievably pleasurable. But at the rate it was going I think it might have taken 4 hours or more to build to something really good. I find that being in these extended states of pleasure that are increasing at almost imperceptible rates can be both hard to concentrate/relax through as well as a huge tease.

Questions...

1. Is this fluttering involuntaries?

2. If so what can I do to prolong or enhance the exhale portion of my movement?

3. Would you consider the fluttering a strong sign of re-wiring?

4. How do you cope with the lingering pleasure pleasure and continue to relax?