It sounds as though your game became corrupt when you were levelling up your wizard. My advice would be to load your last game save before you levelled your wizard up (i.e. when the game malfunctioned during levelling up). If you don't have any game saves before then, then I recommend that you either start a new game all over again, or wait until version 7 of the Circle of Eight Modpack is released on December 20 (the advantage of waiting for version 7 is that it includes a lot of new content including The War of the Golden Skull). As soon as you experience a malfunction while playing this game, it is advisable to immediately quit the game, then run the game (making sure that you have the option Clean Game Cache On Startup activated in the Options menu of the ToEE Front-End X), and then load your last game save before you experienced the malfunction.