I’m having a similar issue just now. Had a surgery on right knee a year ago. Since June added some volume on Oly lifts and squats. Did a lot of stretching to open my hip (super squat, anterior hip openers with a band). Had some minor knee pain in both knees, that disappeared after warm up, but got worse an hour or so after the workout, so walking stairs was very uncomfortable. two weeks ago it got much worse, knees began to swell a bit on lateral sides (where the main pain came from), so I stopped squating and any sort of jumping or Oly to give them a rest.  I found this two vids helpful