You go ahead and keep laughing buddy. Well here in America I live in the northern most region and it would be the southern folk who are the Yanks. It's a bit too north for me to be a Yankee.
I've lived in the States all my life and I've never ever ever known someone from the South to be called a Yankee.
The North, especially where you seem to describe, would be Yankee territory.
Something smells funny about your story, dude, especially if you're confusing a basic fact about America.