I fell down one step and landed on my hands and knees on carpet about 8 months ago, at first it felt like i had gravel in my knee when i tried to kneel, now when i kneel on my right knee only it has an excruciating pain unlike the gravel feeling, more like there is a lump in there , it can hurt so bad it will make me have a nausea feeling for a few minutes from the pain, i am 55 and in really good health, I thought, what would you say, i really only have minimal swelling on the rightish side of my right knee.