I read your post on another thread and I wanted to say a few things, so came here to do so!! First, I do not think it is a good idea to take extra pain meds for PT. For one thing, you could injure yourself without even knowing it. For another, PT should not hurt you!! I never had a minute of pain in PT.
If you are stiff and in pain, then you are doing too much in PT. I really hope the PT is not pushing on your leg to get more rom!! That is a fast track to extra swelling and longer recovery. So, take it slow right now---you employ the PT, so you can decide how much is too much. Here is my idea of a guide---ride a bike for five min---swelling?? too much, ride for 4 min. No swelling? great, ride for 7 min the next time.
Each activity has to be added and increased slowly enough that you will not be in pain or swelling the next day.
Right now, your quads and hamstrings are not strong, so if you have to do a lot of weightbearing exercises, your joint has to help hold up the leg. It complains with pain and swelling. Listen to your joint, not your PT>