Hi, while football training last Wednesday, I swung my leg at a ball that was mid flight. While swinging at it I heard a pop or a crack, not sure of the best description. I immediately felt a pain in my lower quad. I thought it may be something quite serious at first, but then after a couple of minuites the pain subsided and walking crated no further pain. I attempted to rejoin the training session only to find out that once I began running again the pain was again unbearable and I imediatly stopped after only a couple of steps. I can still walk fine on it without any sign of a limp but I also seem to have a dip about 10 cm up from my knee in the muscle. Is it possible to diagnose what I have done and what the injury is from this information? Thank you.