Username or password was incorrect

Hello, i just try to go my admin panel and not can log in anymore and i get this message

Error!
Your username or password was incorrect. Please try again.

and last night that working fine yet but not today anymore so how this can fix how i can login again?

do the forgot password, from the index page, or join page.

 not work because say email not be databace, is there like config file where i can check that my password and username?

 You would have to use myPhpadmin to access your admin profile, there you can change your email, you can assign a new password too but that is harder than just changing something like the email..

http://youtu.be/rsxLYdFpArk

Thanks

your welcome