FYI - yesterday I received my booster Covid vaccination. Easy Peasy - a large group was at the hospital, all over 75. Administrators had doubled up the appointments due to inclement weather coming. A few minutes after the shot I think I felt something in that arm, vague weariness or similar.
No problems since, except a mild headache last night. Today I am groggy and achy altho that's a fairly normal daily condition. I finished hand sewing the binding on "Starry Nights" and managed snow shoveling in ZERO temps, so apparently my parts are all working well enough!