[MangaD]

Your enemies are that level to keep up with you. Other people have cleared the game at a much lower level, as you can see in this thread. You probably played Training too much...

It is not your fault though, this is a serious bug. And if you bought gems only the more reason to complain. So, you can either wait for an update or start over. You may also send an e-mail to Marti to explain your situation (although he's aware of the bug...)