Long story short, I ended up deleting the root user from PHPMyAdmin in EasyPHP. After some researching, I used skip-grant-tables to regain database access. Now, however, I
cHao and Andrew's answers solved the problem for me. I reset all permissions in the MySQL db, user table, to yes. All dbs then reappeared in phpMyAdmin, but I had no 'create db' privilege there. Cleared the phpMyAdmin cookie and even upgraded phpMyAdmin with no success. Then I went into the tmp/php directory and deleted a session file I found there (named sess + random ascii), and success!