Growing, that happened to me, too. The first three weeks, I lost 5-6 pounds a week, doing the exercise bit & cutting portions. It kinda freaked me out because it seemed too fast. Now, though, I've tapered off to a more sensible 3 pound a week for the past 3 weeks. Like Faerie said, it's normal to have the higher numbers when you start but it will go down a bit eventually. =D
The Big 1-0-0
"Walking is the best possible exercise. Habituate yourself to walk very far. The Europeans value themselves on having subdued the horse to the uses of man; but I doubt whether we have not lost more than we have gained, by the use of this animal."
-- Thomas Jefferson