It could also be a meniscus tear or an ACL/MCL issue - both only solved with surgery (no just waiting until it gets better). My mom has had her right knee operated on for the same symptoms and has had NO problems since. You will want to see an orthopedic doctor - In Crystal Lake, I can recommend Dr. Rochell (mom's doc).
No fun to have to get surgery, but so much better than how you feel right now!!!
Unless you change your direction, you will end up where you are headed.
Even if you're on the right track, you'll get run over if you just sit there.