Someone has created an Apple ID using an email address in a domain I own
I think this may be a phishing. I advise you to check the 3 following key
points:


Within the headers of the 2 E-mails you received, verify
they are really originating from apple.com .
Verify the included URL is really within the apple.com domain.
Within the headers, verify there isn't any Return-Path: outside of apple.com .