Damn, CP, that sucks. My buddy had the same in the run up to the NYC marathon, but he's fully recovered now. He ran the same half I did and while not a PR, he considered it a good training run for his upcoming marathon this spring. He even ran a few more miles after the half to get back to his car. Bastard.
6.5 for me this morning.
Sam, if I understand your description, the "100s" have you running one direction on the straight, then turning around and running a lap. Is that right? If so, what's the rationale for the first turnaround?