I got summoned for petit court last June (my first day of summer vacation

) and was totally dreading it. It didn't turn out bad at all. There were 10 cases up for trial that day, all but one was either dismissed or settled so I was never actually selected, but considered for time served.
Cases can last anywhere from 1 day to several weeks, but I think judges really don't want people that have issues with being there. (At least in DE).
Good luck, hopefully you'll be out of there by noon.