The Second COVID-19 Shot Is a Rude Reawakening for Immune Cells.
Side effects are just a sign that protection is kicking in as it should.
'At about 2 a.m. on Thursday morning, I woke to find my husband shivering beside me. For hours, he had been tossing in bed, exhausted but unable to sleep, nursing chills, a fever, and an agonizingly sore left arm. His teeth chattered. His forehead was freckled with sweat. And as I lay next to him, cinching blanket after blanket around his arms, I felt an immense sense of relief. All this misery was a sign that the immune cells in his body had been riled up by the second shot of a COVID-19 vaccine, and were well on their way to guarding him from future disease.
Side effects are a natural part of the vaccination process, as my colleague Sarah Zhang has written. Not everyone will experience them. But the two COVID-19 vaccines cleared for emergency use in the United States, made by Pfizer/BioNTech and Moderna, already have reputations for raising the hackles of the immune system: In both companies’ clinical trials, at least a third of the volunteers ended up with symptoms such as headaches and fatigue; fevers like my husband’s were less common.
Dose No. 2 is more likely to pack a punch—in large part because the effects of the second shot build iteratively on the first. My husband, who’s a neurologist at Yale New Haven Hospital, is one of many who had a worse experience with his second shot than his first.
But much like any other learning process, in this one repetition is key. When hit with the second injection, the immune system recognizes the onslaught, and starts to take it even more seriously. The body’s encore act, uncomfortable though it might be, is evidence that the immune system is solidifying its defenses against the virus.
“By the second vaccine, it’s already amped up and ready to go,” Jasmine Marcelin, an infectious-disease physician at the University of Nebraska Medical Center, told me. Fortunately, side effects resolve quickly, whereas COVID-19 can bring on debilitating, months-long symptoms and has killed more than 2 million people.'>>>
https://www.theatlantic.com/health/archive/2021/02/second-vaccine-side-effects/617892/?
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We had our first Moderna last week, and the second shot coming up in April. I plan to have some easy food in the fridge in case we are hit hard.
Thanks for posting this. 
They do recommend that you avoid alcohol for a few days.
His arm was mildly sore last night. Today, he has no symptoms at all and, because he worries, and because he is married to a woman with a history of crazy reactions to medications and vaccinations, he’s now worried the dose didn’t take. I read this article to him, but he still isn’t convinced. 
Had a small reaction to the first one and then got laid flat for two days with the second.
I have cleared my calendar for the weekend after my second Covid shot on the 25th.
I am such a fragile flower.
I had chills the evening of the shot and some body aches throughout that first night. I woke up feeling great the next morning but went down right at the 24 hour mark with fatigue, chills and a fever...not horrible but I definitely didn’t feel well. I slept 10 hours straight and hit the ground running Friday. I’ve felt great since.
I haven’t had a shingles shot....I guess that’s next!
I had the J&J last Wednesday afternoon and right at the 24 hour mark, I had chills, body aches and fatigue. After a good night’s sleep I woke up like any other day and felt great. Keep us posted!
It sounds like you’re past the witching hour... 
(Speaking from experience.)
You will be fine!
I was good until late this morning,,,, then chills, fever, exhaustion,,,, lasted about 8 hours,,,,, we'll see how tomorrow goes,,,,,
to anyone getting the second vaccine,,, just have some 'easy' food around and don't make any plans be lazy,,,, and hydrate!
Dehydration always feels lousy, even without a vaccine. I’ve had enough wine headaches the next morning to remember that. 
