In October 09 I began having really bad pain in my left knee. I was hitting with a friend when first the arch area of my foot started hurting on both the left and right side of my foot. Ten minutes later the pain was up to me knees and i could barely walk. I did not play much tennis for the next month or so. I thought the pain was gone until 2 weeks ago when the same thing happened again. I was playing a match when the arch of my foot began to feel sore. Ten minutes later im limping because of the pain. I've been active since then and it only hurts when im moving left and right while playing tennis, not when i was jogging. On the first occasion i was wearing 6 month old Vapor 5's, and on this occasion i was wearing 6 month old CB 1.2's. Does this sound like a foot problem or a shoe problem?