Often it happens that you do not add the username and login area to a drupal theme and log yourself out of drupal on your system.
First thing you should try is to type: http://localhost:8888/?q=admin, there are chances that your comp has remembered the password etc...
If this doesnt work,
type in http://localhost:8888/?q=user
Here you will find the username and password area that you can use to type your username and password and move in as admin!
