Cannot Access wp-admin

Hi there,
I believe my problem originated from switching around the location of my site and blog. I have gone through the help here: http://codex.wordpress.org/Changing_The_Site_URL
but haven’t had success.

When I visit my site (http://www.bingaswingas.com), the site works fine. However, when I visit http://www.bingaswingas.com/wp-admin I get the following message:

Warning: Cannot modify header information – headers already sent by (output started at /home/bingasw/public_html/wp-content/themes/neoclassical/functions.php:7) in /home/bingasw/public_html/wp-includes/pluggable.php on line 770

Any help is most appreciated.