I got my Pfizer shot in my non-dominant arm, and surprise, surprise: I ended up having to do stuff at work that required more active participation from that arm than usual.
I noticed some soreness starting a few hours after the shot and lasting through the next day, but I didn't have any serious pain or other noticeable side-effects.
Even so, getting my shot in the morning and going to work afterward probably wasn't the best idea. I scheduled my second dose for late afternoon, so I can just leave work early and go straight home after the shot.