Well I've been dreading it since I started but today was the day. I took everyone's advice and set off nice and slow and it was fine! I actually found it easier than the two eight min runs. I controlled my breathing and had plenty in the tank at the end - in fact, I increased my speed for the last two mins and probably could've gone on for another five.
In a way, I think all the dread was a good thing because it was nowhere near as bad as I'd expected it to be.
On Saturday, I'm doing a British Heart Foundation 5K, and I think it might actually be possible to run the whole thing, albeit very slowly.
My message to anyone approaching this run is that you CAN do it! I weight 17 stone and I'm a smoker, so if I can do it then anyone can!