Https://www.facebook.com/login.php?login_attempt=1

SOURCE: https://www.facebook.com/login.php?login_attempt=1

3 possible errors you made:
*You didn't correctly write your e-mail address(You probablyforgot @yahoo.com or etcc.)
*You mistakenly type your password.(Don't forget capslock)
*You're account was hacked(or just reload the page or re-open your browser0

Hope this helps. Thank you for using Fixya!
-add me up on facebook-

SOURCE: FB Password Reset helpline Call 1-8O5-225-669O We are 24 Hour Available Call Now

Do you have an account on facebook? If not create before logging into it, if have that please tell what error are you getting while logging into it.