What is wrong with me?

So I just got back from a run and the following things happened:

• I successfully competed one circuit around the trail without incident (i.e.: falling down)
• I started walking a second lap to cool down
• While walking, I stumbled over a root. Didn't fall though...
• Thought "ha ha, I will have to mention that on my blog, that I didn't trip while running, but almost fell while walking."
• Decided that I should run a little more, since I wasn't completely exhausted and I'm trying to be able to run farther and/or faster.
• Started running, went a little ways, tripped over a root and wiped out
• Lay on the ground and laughed at own clumsiness/stupidity

I banged up the same leg as on Tuesday (and Wednesday, for that matter) Fortunately this time I missed the existing knee and ankle injuries and hit the lower part of my leg. Giant scrape along the outside of my shin.

Lest you be concerned that I have developed some horrible inner ear thing or vertigo that has rendered me unable to keep my self upright, I will point out that I actually tripped over stuff, I didn't just keel over. But, I have got to find a less root-y trail. Or pick my feet up more, I suppose...

So in 3 days that's a bruise on my knee, a puncture (from the bike chain thing) and a lump on my ankle, and now a scrape on my lower leg. And all on my left leg, I guess I must favor that side somehow. So bumps and bruises and lacerations and contusions. Man, I'm such a spaz.