You were probably pretty dehydrated so your body will hold on to the water, plus this bug throws our bodies all out of wack and it'll probably take some time to get back in balance. I'm 3.5 lbs heavier this morning just because the exits from the bottom end have slowed down. I don't know what the heck caused this, guessing a virus, but it's the nastiest thing I've had in years and very tough to get rid of.