Associate contact with user

Just purchased a MacBook Pro after being a Windows user, and am transferring all my stuff over. There's one annoying error I can't seem to get corrected.

My son and I have the same name. I go by Mike, he goes by Michael. But for some reason, when I set up the main user on the MacBook, I used Michael.

Now my MacBook insists my son's contact card is me. I've used the "this is me" function, and the little silhouette appears next to me in the contact list. But when I first log in, it's not the picture of me that appears, but the default electric guitar that is associated with my son's contact. When I click on his contact card, I see his info, but also see my email addresses and phone. I'll hit EDIT to try and change it, but all that appears is his info. It's like my info is associated with him via a different connection I've been unable to find and sever.

Any suggestions?