Disable all plugins with phpMyAdmin and then try to log in. See https://www.siteground.com/kb/how_to_disable_all_wordpress_plugins_directly_from_database/ for details.
Are you able to access other pages such as http://...pcriot.com/wp-admin/update-core.php , http://...pcriot.com/wp-admin/users.php and http://...pcriot.com/wp-admin/options-general.php but just not http://...pcriot.com/wp-admin/plugins.php ?
Go to your router configuration page, and make sure no-one is connected to your network. That may be the issue. Otherwise I'm not sure, keep scanning your PC everyday just incase you are actually infected by malware that is currently not detected by your antivirus.
cPanel has a virus scanner; run that. If nothing comes up, make a .sql dump of your database with phpMyAdmin and scan that.