4th session – small progress but not there yet

Last night I decided to go for my 4th session and listen to Mindgasm tutorial as many of you guys suggested.
– I smoke some weed
– Took a nice shower to clean up and relax
– went to bed
– put on my headset and relaxed while putting Aneros in. This time it felt so good that I thought I would finally have THAT session everybody is looking forward to.
– Session lasted approx 2 hours – 2 hours of multiple failed attempts. Ended up touching my penis and cuming with a regular penile orgasm
– On a positive note, I got a better understanding of the 2 muscles and the type of contractions that can help reach our goal

1) Mindgasm tutorial is really helpful and made realized that I was doing it all wrong. I got to learn about the lower an middle muscles

*** I dont know what is 75% of contraction – even my 100% is not clear. Should 100% be really strong to the point it hurt ? How do I measure 25%, 50%, 75% ?
*** it was really hard for me to keep my PC muscle contracted for 30 sec. I felt like at some point it was just my sphincter which was contracted and had to put more strenght to contract PC muscle. Am I doing it wrong ? At every “big squeeze+hold”, my PC muscle would shake while I’m holding it.

2) Involuntary contraction: I’m still not sure I what I felt was involuntary contraction. When I would squeeze+hold my body would start shaking, asking for it to stop. Although it was kind of a pleasant feeling, I would not be able to pass that stage. My PC muscle would contract and de-contract as if it was about to give up…

***Are involuntary contractions what I experienced ? Or.. would they happen only if I’m able to hold and pass the stage of shaking ?
***Is it the shaking while squeezing+holding that defines involuntary contractions or would it be the something else (automatic squeezing/contractions while releasing?)

3) Hornyness: although I was looking forward to an amazing session, it was hard for me to get horny and my dick couldnt get hard ; especially with the tutorial playing in background. At some point I started switching back and forth to different horny thoughts and started becoming aroused while squeezing and holding but I would get distracted everytime PC muscle was about to give up. To be honest this was frustrating. I also tried grinding but it was just too many sensation all at once and difficult to focus.

***Do I have to be super horny prior to session ?
***I find it difficult to have horny thoughts while doing the exercise. At the same time, if I dont have horny thought, how am I going to be aroused ?
***Can you achieve Pwaves / Pgasm without thinking of any horny situation ? Like… if I just do the exercise, will I get there ?

I really want to experience Pwaves and Pgasm, for some reasons, it is just tough to clear my mind and lose total control (I tend to control myself a lot in life)

Any advice or comment would help !
Thanks