I'm sure most people know this. The "side effects" of many vaccines aren't from the vaccine itself, but from your body's reaction to it. It's the immune system kicking into gear, recognizing and reacting to the bad stuff. It lasts for, at the most, 2 or 3 days. There's a chance you could be incubating the virus before you got the shot. With the flu shot, there's a chance you'll be infected with a strain of flu the shot doesn't immunize you against. I don't know that that has anything to do with the various Covid-19 immunizations, because I believe they're a different type of shot. It's still gonna be about your own immune system.

And I HAVE SPOKEN. (again)