Just an update. Finished week 2 of C25K and still OK. Unfortunately my diet hasn't gone quite as well as I have gained half a pound due to over indulging at the weekend . I volunteered at the local Parkrun and found it inspiring, males and females older than me running the full 5K. Will carry on with the volunteering until I reach the 20 minute mark and will then join in.
With the support of this forum and the friendly folk at the Parkrun, I now feel confident of getting there.