What's happening to me?

As I write this, I'm at Los Gatos Creek County Park waiting for one of my running buddies to pick me up. Even after skipping Monday's run, jogging extra distance on Thursday, getting a thorough leg-focused massage on Friday and bracing my left knee for a long run, I had it buckle on me again. This morning I was only able to manage 8.3 miles. At least this time around I slowed down at the first sign of trouble. It's still painful but I can walk on it right now with only a mild limp.

I'm really upset because this is the only thing that's keeping me from running further. My mind feels fresh, my heart and lungs are churning, and just this week my right knee was liberated from its brace. I was moving along so nicely and now this – it's true that you really are only as strong as your weakest link. I don't know what's going on. Maybe my knee is misaligned. I'll be going to the doctor on Monday to get it checked out.

I've come too far to give up now.