Horrible stuff, huh! DS and I apparently had the same thing while at WDW last year. He's was only 7, and threw up in his bed around 1a.m., and I got it the next day. Luckily DW or our 9mo. old didn't get it.
It technically only lasted 24 hours, but I felt like I had been beaten up for the next few days...Very tired, and sore muscles.