Got my second dose of Pfizer on Thursday. Had yesterday off from work, which was just as well. I had no major side effects, but I definitely felt this one more. The first jab was nearly undetectable, but the second one was a real Ow. Felt like a bee sting. I had the same nurse as before, so I don't think it was her technique. Other people reported the same thing. Immediately after I got back from the observation period, I put a cold pack on my arm for 2 hours and took three Tylenol. My arm still got sore, but doing this bought me about three additional hours before that happened. It wasn't more painful than before, but it has definitely lasted longer. First time was 24 hours almost to the dot. I'm in hour 47 now and I can still feel a little pain when I lift my arm. I switched up arms so this time was in my dominant one (the right). I developed a headache between my eyes around 9 or 10 pm that night that lasted for a couple of hours; I took 3 more Tylenol before I went to sleep. No problems sleeping; no night sweats, chills or fever. At worst, I felt tired, heavy and stiff. Kind of like you do when you've got a cold, except there wasn't any congestion or coughing. I had a stuffy head for a little while when I first lay down, but that went away. That might have also been from dust mites or the seasonal change in temps. All in all, not bad. I'm glad I didn't have to work the next day but I think I could have, if required--though pushing it may have made me feel worse than I did at home. It was a great excuse to lay in bed for most of the day watching movies, in between bouts of making food. My appetite seemed normal, but I tried to eat fairly light over the two days because I didn't want a lot in my stomach in case I felt pukey. I didn't.
I would advise, if feasible, that anyone getting the second shot (or the first, in the case of J&J) schedule a sick day for the following day. My employer was generous in allowing us an hour each time on the clock to get the shots without having to take time. I was prepared to get more ill, so I would have taken a sick day if I hadn't been off already. You most likely will feel pretty OK, though you might not feel up to your usual activities and will just want to sleep or relax. If you do have to work, at least try to take a half-day or do lighter activities if you can. If your job involves being on your feet a lot or heavy lifting, probably best to avoid that first day after. I'm at work today and I feel fine now.