I actually did it this morning.
Despite a couple of heavy days away on business (heavy = dining / drinking), and picking up a sniffle I actually did it. I even completed the 5 minute cool down, and felt recovered after about 3 or 4 minutes.
I read a lot of blogs about this, and took the general advice of every one and Laura, slow down. Still managed to clock up 3.22 miles in 35 minutes though (cool down was longer than 5, as I ended up away from home). Pace did seem quicker than I thought I was doing.
One thing I really made an effort with though when I got home was to stretch, and that seems to have done the trick. 1 hour later I feel great, and more than a little bit smug!
Run 2 on Friday!