My Pac-Man frog died. :(?

I got this little Pac-Man frog from pet-smart about 2 and a half weeks ago. He was eating a little at first and slowed down eating more about a week and a half later. I know that I had the right tank set-up, I did ton's of reading. He was constantly shedding, Had constipation, and reddish legs. He also stopped using his legs as much. This was my first Pac-Man. I wanted one forever and I don't know what happened to this poor little frog. I have had an iguana for almost three years now and he is happy and healthy and, HUGE. I also have two juvenile bullfrogs and they are great too. I don't think I will ever get another Pac-Man. I also did not handle him, only when taking him out to clean his tank. He was just a little bigger than a quarter... Yahoo suggested that I put this in the reptiles section. Thanks