Welcome to the recovery side. I hope you'll start getting some relief soon. Are you on any kind of Nerve meds? If not, ask your dr. about trying one. It really helped me alot. I was on Neurontin, generic name is gabapentin, and this really worked great.
Your nerves are probably waking up and getting re-adjusted and the pain can be like before surgery or vary some. It will get better though, just remember your only 4 weeks post op and have a ways to go. Hang in there.
I feel bad that you also have knee problems, but try to walk a little at a time and make sure that you get lots of rest. I believe my dr. had said sitting only 15-20 minutes at a time.
Take care and know that were all here if/when you need us