MinnMan, I can’t help you with your injury, but it doesn’t sound like a typical hamstring pull. I have had several hamstring injuries while running track in college. My experience of pain and recovery is much different from yours. My hamstring injuries were sudden and occurred when running at near maximum speed. It would feel like a dog suddenly took a bite out of the back of my leg and stopping from a full on run with one leg was an experience that is hard to forget. The pain in the muscle would be an intense hot/burning sensation that did not subside even when sitting down or standing. The next day there would still be significant pain and building stiffness in the muscle. Just walking would be a task and I would basically rely on the other leg to keep momentum in my stride. Pulling back with the leg for any reason would elicit the pain. The process of healing/recovery would be several weeks while the muscle healed and swelling in the muscle reduced. There would also be a visible pooling of blood behind the lower hamstring area above the knee that would appear as a yellow tinge to the skin with a blackened area that would remain for a while. Believe it or not, one of the recovery therapies was riding my Raleigh Super Course to keep some fitness and create movement in the muscles to assist in the removal of fluids in the leg. Other therapies included standing in a tub of water with ice for 20 minutes then 5 minutes of easy stretching, then repeat. They also had me take plenty of Tylenol. I could begin running again once the everyday pain went away and I did not push the efforts. Returning to running would be slow and distance oriented. Once able, I would do the sprinter workouts but might begin the 200/300 meter repeats by building up from a jog to avoid the harsh sendoff needed to get up to speed. During the recovery there was a dull feeling in the hamstring that always reminded me of the potential of a sudden re-injury of the muscle. I cannot recall re-injuring the same leg during the recovery or having any setbacks. Good luck with your recovery.