I was really nervous about this run, as so many people are, but physically it really wasn't hard! I think lack of confidence and disbelief in one's ability to make the leap to 20 minutes non-stop running is the killer so hearing about other people's experiences is a real help. Thanks to all of you for the encouragement.
Having said all that I appreciate that some people don't manage it first time for all sorts of reasons. My advice would be to see the first attempt as further training, and keep going until you do it.
You get such a buzz out of this run! And now that I've conquered this bete noir of C25k I feel confident that I can complete the programme.