I think it helps to not take a loss of a pound too seriously as well. I like to see weight stay off for a few days, before I'll count a lost pound as "real" - which allows myself the mental luxury of saying the same thing, if I'm up by a pound.
After all, drink a sixteen ounce unsweetened tea, and that's a pound right there. It's not really fat, just some liquid now sitting in your gullet!