The best I can tell you is try to go to your:
yoursitename/wp-admin/index.php
and do an update to 3.2 (I suggest automatic).
The reason I say this is that I recently updated to 3.2 and then my hosting site sent me a message saying I needed to get the new wordpress update. Not paying attention, I did the update from my hosting site (which actually was a downgrade to 3.14) and I ended up getting a very similar (if not the same) error message.
If you do updates on the admin site, DON’T DO UPDATES on the hosting site… is the moral of the story, lol.
Hope this helps!