DENVER (KDVR) — Enough Americans have received COVID-19 vaccines to give physicians a better idea at what people can expect.

Since no one person is the same, reactions to the vaccines will differ. However, headaches, body aches and chills are reported side effects from both the Moderna and Pfizer injections. The side effects are much more desirable than the dangers of COVID-19, according to Dr. Scott Joy, a HealthONE physician at Englewood Primary Care.

“I put a hoody sweatshirt on [following my second dose],” Joy said. “I had four blankets, and I stayed in bed for two solid hours … it passed very quickly.”

Joy said he was injected with Moderna’s vaccine.

“[The] first time, your system is kind of like— ‘oh what’s going on here … this is something totally new,’” he said. “[Ahead of the second dose, the immune system is] kind of waiting for it, and it’s a little bit more prepared.”

Joy said fewer of those who are 70 and older are reporting side effects compared to the younger crowd. Many healthcare providers have been having a day or two of feeling under the weather— a sign the vaccine is working. Members of the younger generations typically have stronger immune systems and more of a “fighting” response.

“You want to prepare for the next day or the next two days to really not have a lot on your schedule,” Joy recommends.

Clinicians advise telling the boss you won’t be 100%— or take a day off work if needed. Joy said plan ahead. Meal preparation, staying hydrated and having a comfortable sweater handy are all simple steps to take. Also, get plenty rest!

“Think about taking acetaminophen— Tylenol— about six hours after you get the dose,” Joy said. “Lay low for the next day.”

After about two to three days, most people should be back at “100%.” Doctors say it’s a small price to pay to gain COVID-19 immunity.

More than 42 million doses have already been administered in the United States.