I had similar symptoms with the first Pfizer injection. The second, apart from soreness in the arm, was almost unnoticeable. I've had much worse from a couple of flu vaccines where I was sick for two days.
Most people have a stronger reaction to the second shot, but it has been hypothesized that those who react more strongly to the first, my have had COVID already (maybe without symptoms).
Same with me. First shot pain in arm for several days. Before the second shot some friends told me to make sure I was well hydrated and not to take Tylonal before the shot. Followed their advice and had no sideaffect except a bit of a sore arm.