I have said it before, and I'll say it again. Saturday night runs are the worst.
At least now I know it and plan for that reality in advance.
Knowing that Saturday night runs are the worst, I planned to go out tonight for a 4km recovery run - just to get the muscles pumping a bit and the legs moving, and to burn a few calories from Shabbos.
On a very slow run, I ended up running 5km, with 2 pit stops, feeling heavy, on a very windy night with a strong headwind much of the way. But I did it. and because I kept it to low distance, I might be able to go out tomorrow morning for another run that will hopefully be better...