You can change your user name if you want to. To quote the FAQ:

How can I change my username? Members can change their username once and only once with no explanation or special permission needed. Simply send a private message (PM) to one of the site's administrators (not DocJohn). Member names have to conform to our community guidelines, be between 4 and 19 characters in length, and not already taken by an existing user. We allow only one username change per individual.