Ridiculously high heart rate + other questions…

I've had my Helix Syn for about a year now but only just now started to use it regularly. I'm progressing pretty quickly and feel like I'm getting in tune with the subtleties, sensations and how to react to them. I feel like I can just get to below the crest and no further so I will keep trying and listening to my body more. But I have a few questions:

-When I begin to feel waves and respond to them my heart begins to pound harder and faster than it ever has in my life. I've never experienced such intense heart pounding, in fact it's a little bit distracting during the session. I haven't seen much about this here but wanted to see if it happens to others or if it might go away as I get more used to it.

-Tips to maintain focus during the waves? I try hard to keep my mind clear and focus on my body during the waves and build ups but frequently random unrelated thoughts pop into my head and throw me off. Any tips to avoiding this? I smoke weed before the session which seems to help me go to 'another world' during my sessions.

-I don't feel the P-tab much. I've found that using my finger to put pressure on the perineum has helped a ton and increases the force that the Aneros puts on the prostate. I can feel the contractions very easily here, and try to respond to them but I wasn't sure if this is a best practice. Could this mean that I might need to upgrade to a progasm? I like the stronger force much more but would love to keep my hands away from the area.