First vaccine shot, sore arm.
Second vaccine shot, sore arm.
First booster, sore arm.
(All of the above had less soreness than a good weight workout might produce. And lasted about 24 hours. No other symptoms.)
Second booster, increased sore arm. (Slightly worse than any of the above sore arms, lasted a little longer.)
I predict that if/when I get the latest all-variants booster, I'll have a ... SORE ARM.