By Dr. Max Gomez

NEW YORK (CBSNewYork) — Now that millions of Americans have gotten at least one COVID shot, we’re also hearing of side effects from the vaccine.

While most are expected within a day or two of the shot, some may crop up a little later.

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It took some doing for most people, but you finally got your COVID vaccine and you knew to expect some side effects in a day or two, especially after a second dose… But four days later?

COVID VACCINE

“I started to get, like, stomach cramps and then I started vomiting … A little bit later I started to get a headache,” Brianti Downing told CBS2’s Dr. Max Gomez.

Downing is a CBS2 producer who thought her side effects were delayed and unusual.

“I thought, ‘This has to be something else. This has to be the flu or something,'” she said.

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Turns out, it was a reaction to the vaccine, which can happen even up to a week after the shot. The most common side effects are: sore arm, fatigue, headache, muscle pain, low-grade fever and, like Downing, sometimes nausea and vomiting.

Vaccine experts remind us that even with a vaccine it’s still possible to get COVID, especially until your immune system fully responds a few weeks after vaccination.

“I would encourage them to get COVID tested to make sure that they don’t have COVID and they’re not potentially passing it on to someone else. But if the COVID is negative and the symptoms are tolerable, they could just take Tylenol or Motrin and wait it out,” said Dr. Jennifer Lighter, with NYU Langone Health.

CORONAVIRUS PANDEMIC

The one true delayed reaction that’s been reported in the New England Journal of Medicine is an unusual rash and swelling of the injection site eight or more days later. They have all gotten better with minor treatment but should be checked.

Lighter also reminds us that some of these side effects could be due to other respiratory viruses that are now circulating later than normal because mask-wearing and lockdowns kept them under control during the winter.

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Downing tested negative for COVID and said her side effects were a lot better than getting COVID.

Dr. Max Gomez