I have been having swelling on and off since mid December 2014. I do indoor and outdoor track and field at my school, but I'm not a runner. I throw shot put and discus. I injuried my right knee at a meet about three years ago, I popped my knee out of it's socket, but it went back in on it's own. It swelled up and remained swelled for days until I was put on crutches and in a few days the swelling was gone. Now the swelling is coming back for some reason. My knee is swollen on and off and it will also swell up my calf. Keep in mind that I DO have to run warm ups and anything else he runners have to do, I just run half of what they do. My mom is going to call the doctor about it. What do you think could be wrong and what do you think the doctor will do to fix it? Please help I'm nervous about maybe having to go into the doctor. (I'm afraid of needles and I've been told by people that it might have to be drained and I'm pretty sure that involves a needle)