Great Progress, Questions, Convulsions, and, um, Peeing?

Hello everyone,
Over the last year I've made tremendous progress and am thankful to the new Helix Syn and all of the support from the members here answering questions in my early going. I don't know that I've had a Super O. In fact, I still don't know how to characterize what's become of my sessions. But I know one thing - they often leave me exhausted and so very pleased.
Let me tell you what is happening in my sessions, and maybe some of you can shed some light on these things, or help me correct some correctables if they're interfering with my arriving at the long sought destination - the Super O.
The sessions are great for me. Not a lot or frequent involuntaries (or butt flutters as I can them) with the aneros moving in and out quickly. Everything is much more subtle now. I can feel a great sensation build within me, a warmth almost. As I hold a stable contraction against that warmth it becomes oh so powerful. It doesn't have the concentrated intensity of a penile orgasm (a million little nerve ending firing all at once), but it is strong in its own right, building to such a high plateau that the pleasure just seems to radiate outwards from inside me. This causes me to convulse my abdomen (I'm not trying to). The muscles tense and I convulse, much like my wife when she's having an orgasm, lol. The feeling is still powerful during the convulsion, however since the reaction of my muslces are no longer firmly under my control it is very difficult for me to maintain the stable contraction that was causing this sensation to build and trigger. After several seconds when I regain control of my muscles I relax them and, once any contractive pressure is put on the helix I convulse again. After a couple minutes I need to rest so everything goes limp. Usually within a few minutes things build up and the process is repeated. I can seemingly do this indefinitely and only stop because I'm tired and my body has "had enough". Here are my questions though.
1. By allowing these convulsions (though I have no idea how to stop them now) am I eliminating the possibility for the aneros to take me over the edge?
2. I have never had a dry or wet orgasm with the aneros, and by that I mean the SAME sensation of a million little nerve ending firing at the tip of my penis. I have had the general euphoria of, and the same feelings (buzzing, tingling) as an orgasm, but the intensity is not the same as a penile one and it is definitely centered internally or in my rectum rather than in my penis. What is this?
3. During these convulsions my involuntary response is to bear down. I seemingly cannot stop myself from this response. The result is three-fold. First, as mentioned above its impossible to "hold" a stable, medium contraction when my body is trying to push out. Second, at times this is so strong that the aneros actually comes out (and obviously ends whatever it is that I'm experiencing at that moment), and third, the bearing down also makes me pee at times. Not a full, open spigget pee, but some dribble, weak stream, or once or twice a rhythmic mini-fountain. Lol, what the heck is that, has that happened to anyone else, and I'd really like to be able to experience this without needing a towel around.
Any input any of you can bring as to where I'm at in the journey, or comments/remedies for the particular effects I'm experiencing would be greatly appreciated. Thanks!!!