The only place we need to push ourselves is to build muscle in the gym when training for athletic sports!
Our knee replacements are incredibly invasive surgeries that have cut into muscle, tendon, ligament, bones, etc. That needs opportunity for healing. Healing.
The increase in activity will happen after healing. You need to be kind to yourself and to the injured knee. When we are injured, as after a car accident, we are not told to get up and at it - we are told to take care of our injured parts.
Swelling is never a good sign.
Please listen to your fellow Bone Smart advisors. I had the kind of PT you have. He pushed and hurt. I believed the "no pain no gain" myth.
I'm now dealing with Arthrofibrosis and my knee has continued to deteriorate, including ROM - down to 30 degrees. My knee is now worse than it was before the surgery,