Value of Participating in a Running Event

I've got this 5K coming up and I can't let this slide continue. Got myself out of bed went for the run. The first quarter of the run was horrible. I thought I lost all of the little bit of conditioning I had gained. But suddenly I started to loosen up and everything started to feel good. I felt like I could run a little longer with a little less effort. Heartrate was running in the 144-161 range but breathing was quite easy. I finished up the two mile run in less than 30 minutes. Still way off 5K condition but considering I was almost dead yesterday, this was pretty good.