Well, the title pretty much says it… I had 2 SPS (jep, not the numb feeling, but the real SP) through Auto Suggestion (damn fast actually, i said it to be 10 mins and it worked) but i noticed, that when i have it, it is in my chest, then goes to the legs, then to the arms… and thats the problem, they just keep moving anyways… regardless if i want them or not… is there some way against that? Also, no HI came to it… perhaps because i was too awake, who knows. But my real problem is the arms 
In your position I would try to tense all the muscles in my body before starting the relaxation process. I find that can often make the muscles feel more relaxed and prevent them feeling uncomfortable later on, perhaps it will help. 
I do tense them like you said i should, but it won’t work… i even tried to autosuggest them to stop moving on their own but they still do… also they aren’t uncomfortable, they just keep moving when i try having them to just lay on the bed… 