Arrgh My knee!

My right knee is hurt. Went to the gym this am and felt an odd twinge of pain in the popliteal area. I tried to walk and stretch it out a bit then sat in the steam room for a while and went for a slow swim. It seemed to be ease up. So I went to work and was five hours on my feet. Then, a little tentatively, (big mistake!) drove to SF for Rmax at 8pm. Sometime later doing ground work I felt my knee lock up and the pain was intense. Some of my own myofascial unwinding work and Marty's Z-health neuromuscular work freed the leg up enough to where I could move enough to limp to the car and drive home...angry at my inattention to the first signal of trouble that morning.