New Member q,s

have a couple newbie q,s i hope u can help me with..purchased the (helix) and the first couple of sessions of course i thought i was gonna see stars and all u hope for when u first purchase from reading the threads.Of course my fist 2 sessions i tried all the positions and different things i have read here with no spasms or anything i would call close to small o.s or anything exciting at all.On my 3rd session i was more relaxed and of no hopes,i found that on my back and with a towel positioned under rump so helix wouldnt move outward , i felt more in tune with the helix, I had a nice rythm going like it was sliding in and out of me but of course it wasnt, so my real q,s is the muscle u use to stop from peeing i use in rythm of squeezing of the sphincter muscel.Is the prostate actualy above or below that area so i know were to concentrate movemenet on.Im tall and slim and wondering if im not going deep enough or maybe need the larger model? any advice would b nice thanx