Some friendly advice....
The first month post-knee replacement is accompanied by a profound loss of lower extremity skeletal muscle size and strength that's hard to recover. The pain will be gone, but it takes almost a full year to recover what you lose in that first month, if you even get it back.
There's a really good PT that does high-level research into getting folks back to full function post-knee replacement at UC Denver (J. Stevens-Lapsley). She's doing the best research in the field right now focused on early, post-surgical rehab approaches to mitigate strength/function losses. If you're not close enough to Denver, you might ask your Ortho surgeon or PT to look into it to prevent those early, post-surgical losses.
Best of luck,