Did pull or tear something in your knee?

Speaking from experience, you will feel intense pain around your knee at the time of incident. This will be followed by swelling. If it feels like your knee is unstable after the swelling (the swelling was supporting the joint), then you probably have a complete or near complete tear of a ligament. The ligaments and cartilage of our body will NOT heal themselves as other injuries. Depending on severity, you will either need knee surgery or physical therapy to develop the muscles around the knee to make up for lack of support.