I've had both series; Zostervax and then Shingrix. Little to no side effects from the first ones, but Shingrix took me down both times. The nurse at my doctor's office warned me as she was about to inject me. She said, "I'll bet Dr.... didn't warn you, did he?" FTR, I had significant symptoms from both Moderna vaccines and the booster. Just one of the luck ones I guess.