Actually, it sounds like you might have joined a group? If so, go into your group list under "communicate/contacts/groups", select "none" and click the activate button. Whenever you join a new group, it is automatically activated and you'll show whatever title (tag) above your name that the group owner has set for it's members.
If you didn't join a group, then yes, you may be wearing a "titler" as Cinnamon suggested.