This condition was completely new to me until my friend died last Monday due to Pulmonary Embolism from a blood clot probably in her leg. She had a fall down stairs and injured her hamstring. A trip to the emergency room failed to diagnose the problem. She was in intense pain. She died two days later. I suggest you see a doctor immediately as there is diagnosis and treatment for this. There is also much info on the internet on the subject which includes symptoms, etc. I found it under Deep Venous Thrombosis. Good luck.