WP-Admin Page Missing After Editing General Settings

Could someone please take a look at http://www.A-1Locksmith.com/blog/wp-admin and maybe tell me why my wp-admin page is no longer available? 2 days ago I was in the admin panel and I changed the site url from http://www.A-1Locksmith.com/blog/wp-admin to http://www.A-1Locksmith.com/wp-admin and instantaneously the admin panel went down. I haven’t been able to login since.

ANY advice would be great and MUCH appreciated.

Regards,

Jason