Hopefully 8 minutes shouldn't be tooooo bad on Tuesday, but the 20 minute run still sounds like some kind of sick joke at the moment...
) but I am also due to do the '20 minuter' (or at least attempt) on Friday morning too. AND, to add to that, I had to laugh when I read your comment about the 20 mins seeming like some kind of "sick joke" because those are the exact words I used when telling my husband about the next run! Weird....... Well, maybe we should synchronise watches for Friday.......... 
Hope you are now fully recovered. Like Toadie says, don't be down hearted about having to repeat a week - it's great that you have managed to get yourself back on track again. I had to repeat a couple of runs on one week (week 3 I think) and, although I was fed up about having to do it, in the end it turned out it really built my confidence. 
That's normally the time that I am lying in bed, psyching myself up! So, I could be a little behind you..... Are you in UK i.e. same time as me?? 
“Suddenly, I was part of something. I was part of the running community. The more open I was about my running, the more open others were about theirs. I found out that runners love to talk about running.”