Ok, I ran my first 10K with a wicked hangover and 3 hours sleep and still came in 5th (my sister came in first and she was still drunk I think) Now mind you I was younge and stupid and being punished by my mother and my sister and I had lettered in cross country and track 3 times. But, if you have been running you should be fine, don't ask more of your body than it can give this first time out. If you can't finish it running, no harm no foul, just a learning lesson walk it off, and try again.
Good Luck, and don't forget to stretch





