I Have A Strange, Tingly Feeling In My Knees Whenever

I have a strange, tingly feeling in my knees whenever I am relaxing. When I sit, relax or try to sleep, the tingling starts. It happens every day. The tingling sometimes gets so severe that I have a frustration to move my legs. I have to continuously stretch my legs to get relief, but as soon as I stop stretching, the tingling starts again.
The tingling is not fun, it is very uncomfortable. My knees pop a lot of the times too. If i hold and move my knee cap left and right, continuous pops and cracks emerge. The knee-cap movement also gives relaxation. I also have the same feeling in the elbows(sometimes). Please help.