Custom Page Type (Document Type) Editing Form Value

Ok, having a tough time with this one, reaching out for a bit of help.

Basically I have a Page Type (Document Type) called StateProvince. When A user wants to add a new state or province, I allow them to select a state/province from a drop down list. If the state/province already exists in the Page Type then it is filtered out of the drop down list, except if it is the current Page Type (StateProvince). The problem is, is that I am not resolving the current form DocumentName unless in the Page name source field I set it to "Use extra field". which I do not want, since the document name cannot be free form text. Here is my query for my drop down list.

Select StateDisplayName AS StateProvince, StateDisplayName FROM CMS_State WHERE StateDisplayName NOT IN (Select DisplayName From HOD_Places_StatesProvinces WHERE DisplayName <> {% "'"+ DocumentName + "'"%}) ORDER BY StateDisplayName ASC

Additionally I am unable to resolve any macro's to the current document on the editing form for any field on it, to get the value.

I guess all I need to know is how to get a fields value on a page type standard editing form, while in CMSAdministration.