PooDhay, I forgot about that damn CPM, when they tried it in the hospital, I didn't realize they had it set to fast. I had finally gotten my heart rate of over 160 post - op calmed down, my PCA pump needed a higher baseline, and they strapped me in this thing and turned it on. oMG. I just cried, and cried, begged them to stop!! They finally stopped, tried one more time, much slower, meds were good, I fell asleep with it. It came home with me, I hated it then, my knee was swollen, my pain meds screwed up for the first 6 days, it hurt, but I tried. I do not think it is meant to hurt us. My Pt slowed the speed WAY down, and it was tolerable. Don't beat yourself up is right!!