I hurt my left calf muscle early in the season, but after that healed, I was riding fast on a group ride and felt a sharp pain in the back of my left knee. I've had recurring pain on and off in the back of my knee since and I can feel the popliteus is sore and swollen (a PT friend confirmed this). I rode a century last weekend and it started to hurt after the first hour. I've been icing it and wearing my calf compression sleeves ever since. It hurts less than it did, but it still aches even to walk for more than 10 minutes. Any idea what's causing the pain or tips for recovery?