It will probably take more than two weeks, give it time. The three times I've gone off prednisone, the moon face was one of that last things to go - sorry. That can take months. Probably some of the weight gain was water weight which may come off within the next month or two. One time I noticed there were about
four or five days that I was peeing nonstop and I think that was my body getting rid of that excess fluid. Hang in there and it will come off eventually. Sounds like you are on the right track.