I Have Knee Pain. I Was Told That My Leg

I have knee pain. I was told that my leg is bowing. Hurts all the time. Six years ago I had a bakers cyst on backside of knee drained. Was given a series of three shots just below that knee of something that might help cushion ( sorry, I can't remember what it was called!) The knee sometimes swells. Difficulties with stairs, raising myself up from sitting position. The one knee will not fold back completely.