chrisnewell4444 on "wpmarketplace site load error"

I activated the wpmarketplace plugin today, and now my site doesn't load - gives me a 500 internal error. The error log from my cPanel says the following:
[17-Nov-2013 20:15:32 UTC] WordPress database error Duplicate entry '1' for key 'PRIMARY' for query INSERT INTO wp_mp_payment_methods (id, title, description, class_name, enabled, default) VALUES(1, 'PayPal', 'PayPal', 'paypal', 1, 1) made by activate_plugins, activate_plugin, do_action('activate_wpmarketplace/wpmarketplace.php'), call_user_func_array, wpmp_install

Is my assumption that activating this plugin caused my site to be unreachable correct? Site is http://TheSeniorAgent.com

Thanks