Hi, I'm 24, female. I don't walk much. But whenever I walk for more than 5-10 mins, my left knee hurts.. The pain is on the left side of my knee. It starts slowly and after a few minutes I can't walk any more. It stays for a few hours, and hurts whenever I try to bend my leg. The next day I'm usually fine. This has been happening for few years now. I think it's because I never move my body much and I don't stretch my body before walking to school. But why is the pain only in the left knee, why not the right one? please help. Thanks.