Cannot log in with created user in mysql

You probably have this perpetual MySQL problem where one of the default users in the user table is '' @ localhost, which winds up denying all localhost users later in the table. What I would do is mysqldump the mysql database and look for this entry in the User table; if found, delete it and flush privileges.

For more details see https://dev.mysql.com/doc/refman/5.5/en/connection-access.html.

It is a common misconception to think that, for a given user name, all rows that explicitly name that user are used first when the server attempts to find a match for the connection. This is not true. The preceding example illustrates this, where a connection from h1.example.net by jeffrey is first matched not by the row containing 'jeffrey' as the User column value, but by the row with no user name. As a result, jeffrey is authenticated as an anonymous user, even though he specified a user name when connecting.

This is a problem caused by the anonymous users. Once I install MySQL I always run

shell> mysql_secure_installation 

and select to set/change the root password, remove anonymous users, disallow remote root login, remove the test database. This will remove the anonymous user and secure your installation. It should also solve the problem you have.