Lost my admin page

To begin: I am an internet novice. At times, even WordPress confuses me. I was recently messing around with the settings, trying to get my registered domain name (www.maxphotostudio.com) to redirect to my WP blog; I want to use it as my new website. As soon as I changed “WordPress Address (URL)” to my from http://www.maxphotostudio.com/wordpress to http://www.maxphotostudio.com and applied changes, POOF! I now cannot even enter my admin panel to change it back, I can’t do anything! I cannot for the life of me figure out how to get things back to the way they were. Help!