I remember my Facebook password but have forgotten my ID and user name. How can I get them back?
Last time I checked, I use my email address or phone number to log in.
Do you know the email address you used to sign up? Have you assigned a mobile number to the account? You can recover using these methods too.
Just go to the homepage, click Forgot Password and enter your mobile/email/username. There's also a link to help you identify the account.
Ask your friend to get your username by going to your profile from his profile.
Your facebook username is listed on the facebook URL for your profile. So, get one of your friends on facebook to visit your profile and give you the URL. For example, my facebook URL is facebook.com/kev.quirk.3 so my username is "kev.quirk.3" without quotes.
Once you have your username that should be enough to login. Also, you can login with your email address, not just your username.