Glad it's going better, stick with the plan of 8k Friday, but make sure to take it very slowly. Do the 22 on Saturday but factor in planned walk breaks - schedule them ahead of time. We intended to do a couple of these sessions so this is probably a good time to start. How about:
run 18 minutes walk 2 minutes? Alternatively, run 9 minutes walk 1 minute. The usual exception is if you hit a hill take the walk break - no point thrashing yourself uphill and walking down the other side. It'll be a longish session so take water and maybe a flapjack / gel with you.
I just did my first hill training session in over a year - very nice to be back training with other people, even if all I see is their backs as they lap me . I'd forgotten how hard it is and how much effort an extra couple of kilogrammes of weight requires, but I just about finished the session (with a couple of walk breaks). Feeling good now, suspect I'll be a little stiff tomorrow.