Can someone please try to diagnose this injury. I have been doing around 45 miles a week, went for an easy 6 mile run with a few hills in it, and woke up the next day with a pain to the left of my knee cap. I was able to run 5 miles on it without any pain at all, however, it is painful to walk on. I have been icing alot. But any ideas what this could be? I have been injured often but the injuries usually hurt more when I run on them.