Getting locked out of Facebook is frustrating and it can take days to regain access to your account.
Take a minute and check that Facebook has your current email address at https://www.facebook.com/settings
I also recommend setting up Facebook's "Trusted Contact" feature, in the event that you should get locked out. Your trusted contacts are friends you chose who Facebook will contact to verity that you...are you!
It's always a good idea to review your security settings once or twice a year. Things can change at your end, and Facebook often adds new features. It just takes a minute, but can save you days of frustration! https://www.facebook.com/settings?tab=security