I think in the beginning your body freaks out that it isn't getting the same amount of food. So it hoards even more.
And then when it realizes that the change is permanent, it starts to use the fat stores. So just wait it out. And remember to be regular with your meals because then your body won't go into panic mode again trying to hoard food because it doesn't know when it will get food again!
Good job on getting started though! Good luck!