How Is That Possible?

Okay, I walked 4.5 miles a day in Disney and came back 3.5 pounds heavier. I got a Wii last week and began sweating it out almost every night and have dropped NO WEIGHT. For the most part I’ve made healthy choices in food (except last night - I had a nice hamburger with onion rings and a milkshake - what? I’m PMSing right now). Last night I spent 2 hours playing tennis and boxing on the Wii - had a nice sweat going. Weighed myself before going to bed. Got up this morning, and has .5 pound HEAVI