Over the weekend, I felt as if I'd pulled a muscle behind my knee. I used ice, and it was completely gone by Monday morning. I did skip my Saturday workout and did lowmax, step only portion, on Sunday. On Monday, I did Rhythmic Step because I was still afraid of really high impact (I was dying to run), but that was a little too much and the muscle hurt briefly. Again, ice alleviated the pain. The pain started when I doubled up on Karen Voight's Long Lean Legs on Thursday and then on Friday, I did Hardcore Extreme. I think I just overworked my hamstrings and knees. I also did NOT listen to my body. When I felt the first twinges of pain, I just ignored it. I hope this helps. I rarely answer posts. I just lurk, but I was just so amazed to see that someone else had a similar pain. It seems like it's in a weird spot.
Gretchen