I know exactly what you mean by falling off a ladder. Granted, I'm not a doctor, but that is exactly how I would describe feeling with a stomach flu.
Definitely wouldn't have an appetite either! I know it's common sense, but do drink plenty of water/gatoraid. Being even just a little dehydrated makes you feel so much worse. The last one I had kicked my butt. I didn't eat a full meal for 2 weeks afterwards, and I've never felt so close to death! (drama queen
) Sleep sleep sleep!