Well whaddya know? I actually did it and it's all thanks to you wonderful people on this forum! I was all set to repeat W5R2 as I didn't feel ready for the 20 minute run but after reading how others had surprised themselves and smashed it, felt I should give it a go.
The first 12 minutes were the worst but suddenly found my stride and finished the run with a flourish of speed! It felt amazing but I couldn't have done it without you all, so thank you all so much and to those doubting themselves, just go for it !!!!