I fell flat down in a store on my face, broke my tooth off, mouth was in a lot of pain, I had previously had both knees replaced and was having some stiffness in my knees but after the fall my latest replacement knee began to give me more pain, of course it did swell from the fall and developed a lump that has just about gone way, it was also swollen and bruised. now when I walk a distant, get out of bed or from a sitting position I have pain and a lot of stiffness sometime I need help to get up. could this be something serious?