I just re-read your last post and see that you were up when that NA moved your leg against your will. Don't let them sit you up in a chair again. When you aren't walking or making bathroom trips, your place should be in bed, resting and elevating your leg. And whoever heard of sitting with a totally straight knee, unless it was properly elevated?
Get your pain control sorted out and go home - are you sure that doing too much exercise and doing injudicious things like sitting up in a chair aren't contributing to that pain?. I was in hospital for 5 days after my last TKR and for the first 3 days I did nothing, except walk to and from the bathroom. My leg was so swollen that it wouldn't bend at all and it certainly couldn't do any exercises except ankle pumps. But by Day 5, Some of the swelling had gone and the leg moved more readily.