The pain will vary depending on where they are cutting. Abdominal surgery tends to be quite painful the first 12–24 hours after surgery and then the pain should decline considerably. I think I took one pain pill after I left the hospital and that’s it. I was very sore for 4 days when I moved though. Best to have someone there who can wait in you hand and foot for a couple of days.
If you are going to be hospitalized over night have someone visit and be able to help fight for you if the staff is fucking up.
The first 24 hours after the surgery are serious no matter how minor the surgery and any feelings like you are having some odd horrible thing happening counts. Don’t ignore weird pains, a fever over 100 (slightly elevated temperature is common) and any other out of the ordinary things that are not outlined in the information you were given.
Be sure to read all the information you are given about what to expect.
Nausea is very common after being out under general (are they using general? A block? Just some IV sleepy forget me drugs?) and there are drugs that can counteract the nausea. Since I am phobic about throwing up this was very important to me. Women tend to get nauseas way more often and more severly than men though, so it might not be a big deal in your case.