Hello, I feel like I have an air bubble lodged underneath my knee cap. I bent my leg wrong during a game of Twister, and now I can t bend my leg more than 120 degrees, after which I feel like my knee cap is going to dislocate. This is excruciatingly painful, I get a very cramp-like feeling with a high amount of pressure on my knee. What could be the matter, and what should I do?