Knee effusion? Supra-patellar bursitis?

So starting last year, my right knee started giving out, extreme pain and could barely walk- also swelling at top of knee/bottom of thigh area. In fact this is what had left me to Rheum anyway- the ortho found nothing terribly wrong- nothing torn etc., just arthritis and some cartilage wear. And then he gave me a cortisone shot and some Mobic and sent me to a Rheum. those did help some, but now I am back in the same shape again!!! Incredible pain and stiffness, with some swelling. Sadly my insurance changed and I know have to see a different doctor at a clinic and not for 4 weeks. I'm suspicious about this- what is happening? I am being diagnosed with Fibromyalgia and Sero-negative arth., so could this be inflammation from these conditions? The Rheum barely acknowledged it- with a little fat shaming, but I'm not that overweight. I am chalking it up to not being her specialty.
My right knee is the worst, but I also have left knee pain and developed a LOT of weakness in the last year- I can barley climb a flight of stairs- in fact this started a few years ago but I wrote it off...
Anyone else?