What Causes Swelling In Knee Along With Tingling Sensation?

Hi I fell on both my knees about two weeks ago. X-Ray shows no fracture. My one knee is still swollen ,tight to touch and slightly warm. When I touch the area of feels tingly. No blood clots I had a sonogram.I have difficulty walking unless it s wrapped in an ace bandage. What do you think that is? I am 60 and when I fell both knees were very black and blue. Thank you.