Sadly no , if I could , I would changed it a LOOOOOOONNNG time ago but tho well. You've just started so I suppose you still can restart a bit. If you wanna , just deactivate the account , start a new one with the name you want and there we go. New name.
No. You can't anymore but as of a few months back you could. There used to be an option to contact Help and request the change but that has been eliminated now, think it was last allowed back in March or so. Since then, here is what it says in Help/Account: http://www.girlsaskguys.com/faq/account
"Unfortunately no. Recently we have changed our policy and do not allow username changes anymore. Username changes have been starting to become more and more popular and these changes have been creating confusions among users. So, no more username changes. Thank you for your understanding."