Greenlake half marathon

I ran my first half marathon yesterday: just over four laps around Greenlake, or just over 13 miles. What an ordeal.
Dave ran the first lap with me, and all was well. Partway through my second lap, I had a gastrointestinal emergency and ran my fastest mile split in racing to a public bathroom. One stall, no door. Lovely.
Having overcome that, my third lap was shaky. My knees felt really stiff and sore, and my left ankle started to sting. Before my fourth lap, I stopped at my car to eat a Clif Shot and pick up my iPod. The sun had set by the time I set off for the final lap, and I started to shiver. I had also forgotten to bandage/apply Vaseline to my nipples and between my legs (yes, these are the gory details familiar to long-distance runners but not yet second nature to me). There was a traffic jam of pain signals from all around my body up my spine that last lap.
I staggered in, bowed by not beaten. After a bit of stretching, I limped over to a supermarket and stocked up on Gatorade and some Icy Hot bandages, one for each knee.
My limiting factor remains my knees, and to a certain extent my ankles. The lungs feel fine, though I'm still a tortoise. I'll miss Greenlake and its outer path of dirt and gravel. It's softer than pavement, and for the most part it's level. If they'd only install some more lights around the perimeter it could be a round-the-clock training route.