[Plugin:Facebook comments for wordpress] error message on home page & dashboard

Was testing out FB plugins and after activating Facebook-comments-for-wordpress (I believe this was the name of plugin) I receive this error message:

Fatal error: Cannot redeclare class FacebookApiException in /home/content/01/8346901/html/wp-content/plugins/facebook-comments-for-wordpress/scripts/facebook.php on line 91

At first this error only occurred when I tried to use the admin login, then it occurred on links within the website, now I cannot access my homepage. As such, I cannot login to WP admin functions or view my homepage as a normal user would.