I don't understand what else you were expecting.

The 15 min wait is because some known side effects manifest within those 15 minutes. Everything else is either minor, or extremely rare, or both. The US has the VAERS system if you want more on side effect reporting, but your doctor is supposed to do the work.

Either way, the vaccine was tested. That it didn't go through a 10 year trial period is because we didn't have the time. Will you suddenly explode or combust in 11 years? I can't prove you won't. I would happily put money on the negative though, care to wager?

That's mostly to watch for allergic reactions, which if you get you need medical assistance asap. Nothing to do with the covid vaccine itself.