Well that was surprisingly tough even though it wasn't another 20 minute run! Just had to keep plodding along but now I'm wondering how on earth I got through that 20!
I had done a parkrun in the past and it has changed a bit so I requested my barcode and links today. It showed me that the one run I did almost exactly 3 years ago was completed in 30:13! How the hell I managed that then I don't know as I certainly wasn't doing any regular running or training!
Now I just have to work my way back up there again, get the 30 minutes running under my belt and then maybe try another parkrun local to me.
I won't aim to beat that time, I'll put that down to being in my early 20s then!