Real Housewives of D.C. star and White House 'gatecrasher' Michaele Salahi claims she didn't short-change a plastic surgeon who is suing her over an alleged unpaid bill, Breaking Celebrity News is exclusively reporting.

EXCLUSIVE DOCUMENT: Read Dr. Singh's Lawsuit Against Michaele Salahi

Dr. Navin Singh of Ivy Plastic Surgery Associates, LLC (where he is a partner) and Michaele are due to square off in a Virginia court on Friday, September 17.

WORLD EXCLUSIVE PHOTOS: The Salahis Private Photo Album - Photos With Famous Friends: President Bill Clinton & Jay Leno

The doc alleges Michaele made a partial payment for going under the knife; Breaking Celebrity News has learned it was a collagen placement procedure to fill "laugh lines" on each lower cheek.

Dr. Singh told Breaking Celebrity News Michaele stiffed him over $500: "She had a