I have been having a problem the past few days with my knee/calf while I run, and I can't figure out what the problem is. It started a few days ago when I was doing my long run of 16 miles. Around 12 miles my left knee started to hurt in the back. I finished the run, but it was really tight and sore. I iced it and took some anti-inflammatories and it felt better the next day. I have run on it for about 3 days without much more than a little tightness. However, today I felt some pretty nasty pain in my upper calf on the inside. It was close to where shin splints occur, but it was a little too far back on the leg to be shin splints. It is a different pain than I felt a few days before, but I am sure it is related because of the proximity to the original pain. I'm not familiar with injury at all because I have been lucky enough to stay injury free for the 9 years I have been running. However, I am reasonably sure that it is a soft-tissue injury. If anyone can shed some light on what I have going here, I would really appreciate it.