When I am logged into the Omeka Administrator's site, I am told that I have no items in my archive. The collections I've made have also disappeared. While the tags I've made are still listed, they don't take me to any documents. On the public site, however, everything appears as normal. I can access all records.
Does this apply when you're logging in as different users?
As long as you're on the same actual site, Omeka really can't load different data for the admin and public sides. There are some reasons you might see no items with a particular user, though. (Contributors, for example, can't see non-public items, even on the admin interface).