I've had knee problems my whole life. On Monday I fainted, and while I fell, my knees twisted...or something, not sure what, didn't pay attention at the time. They don't hurt four days later, but now one or both of my knees will lock for a brief second and throw me off balance so I almost fall. It varies, but if I walk more than a few minutes they'll do this at least once. Does anyone else know what I'm talking about, and/or know how I can help my knees get back to normal?