I've been into AP, reading up on it and learning about it and tried a few times but could never really do it, though I tried again, with no bothers around me at the time and doing some techniques I picked out, such as concentrating on breathing and the imaginary rope, after about 15 minutes my dog barked and was forced to get up, but when I did the top of my arms were numb, and the joints in my fingers were stiff, am I doing it correctly up to that point?