I tripped and fell directly on my right knee 13 days ago. I thought that I had just bruised it really bad, but for the following week, the pain got worse.I have been walking with a limp since then because it still hurts to put my full weight on it. It is still really tender to touch my knee cap and the area on the left side of my knee. I went to the er a week after my fall and the exray didn t show anything, but they diagnosed it as a sprain. Yesterday I tried putting more pressure on it, but started getting a burning sensation inside of my knee. I am 5 ft 2 in tall and weigh 111lbs so it s not an overweight issue. Is this normal for a sprain? If not, what else could be going on?