Hacking

I'm not really sure about this, but I suspect that someone else is trying to get on my Facebook when I receive an email notification from Facebook saying that they are sorry I am having a hard time getting online, and it reminds me the options I can take to retrieve my password in case I have forgotten it. In fact, I never had any hard time logging in and I definitely know what my password is, so that only means someone is trying to get in it and can't do so.

Go to Account Settings Security Login Notifications : There you can set a email notifications for it.

well not really, if the hacker was trying to open your account by entering invalid email and password it can temporary block or you cannot open it for a few hours if someone tried to access it many times. You can use Login Notification to determine the locations of where you been login your account. Go to security setting Security Login Notification Enable. Also check the recognized devices, you can see the details of you enter on your login notification and the date when someone login your account.