Access denied for user 'me'@'localhost' (using password: NO)
Now you can probably login by

sudo mysql -u root -p


and entering the password from your ALTER USER statement when prompted.

Once you're in the console again you can reset the password to empty like:

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '';


And it should start to allow you with just sudo mysql as before.