I would certainly try to get those temperatures up to at least the upper 70s if at all possible. Good job on the heatpad, they are a Pacman Frog's best friend.

With the deflation, it looks pretty normal with the description you gave. They "inflate" when they soak, and after they get out they may appear to shrink. That shouldn't be a problem.

I didn't realize that you had a Pacman Frog, yet. How long have you had him/her? He sure is a cutie!