If you want to know Is Facebook is down for everyone or just me? You need to check specific website is in accessible for every one or only for them.

You need to remember several ways to check: -
Try a different browser
Switch off your internet modem and wait for 10 seconds for restart it
Restart your computer.

Read more https://onlinegeeks.hpage.com/what-caused-facebook-to-go-down.html