I oubt the plugin will change your site URL. Can you please check your wp_options table and look for the siteurl and home options – please check these are both set to the correct URL.
Can you log-in to the admin area still? You may need to refresh your permalinks. If not, try to rename the plugin so that it gets disabled and see if you can access your site again.
If there is a problem with the plugin itself, you should ask for support via their forums / email as it’s not on-topic for this site.