My husband and I were scheduled for our second vaccination tomorrow, we live in SC. We received a notice this morning that our appointment was cancelled due to shortage of the vaccine and would be rescheduled within 42 days, (weird number)) It was fine with me.
42 days is the new guideline from the Federal Government for the second shots (it used to be 21 days for Pfizer, 28 days for Moderna).
They likely mean 42 days from the first shot, not from today.
They still try to do second shots on the 21/28 day delay, but they now have official leeway up to day 42.
Freeper lightman recommends taking tylenol with the second shot, to reduce side effects.
Most people who experience side effects from the shots (hangover-like or flu-like symptoms), experience them only after the second shot (shows its working - the immune system mobilizes strongly).
Generally, a few hours to a day after the second shot, it is best to plan on just relaxing, especially if you are older. A lot of folks, including folks in their eighties, don’t really experience much from the second shot, but it is still probably wise to not schedule any commitments.