I had my Covid 19 2nd booster shot (4 in total), and had a reaction that wasn’t listed on their leaflet of possible side effects.
I then went on online, and there it was: Vivid, lifelike dreams, similar to hallucinations.
My first 2 shots were Moderna, and my first booster was Pfizer. I had no reaction to that one.
I do have nightmares most nights, but rarely remember them, and if I do it’s gone later in the day. A week later, and they are still so vivid in my mind. I had animals that were in 3D right in front of my eyes attacking me. I was fearful for my life. I finally woke myself up, and then didn’t go back to sleep for the rest of the night.
There are so many different possible reasons for it online, and I didn’t feel any different when I had this one. This is purely for your information; in case it happens to you. It only lasted the one night, and I was fine. No other effects whatsoever.