Most times, it's not a login issue, but an issue with creating the database itself. So if there is an error creating your database, it would not be created in the first place. In which case if you tried to log in, regardless of the user, login would fail. This usually happens due to logical misinterpretation of the db context.
Visit the site in a browser and REALLY read those error logs, this can help you spot the problem with you code (usually conflicting logic problems with the model).
In my case, the code compiled fine, same login problem, while I was still downloading management studio, I went through the error log, fixed my db context constraints and site started running fine....meanwhile management studio is still downloading