How do you know if you've been blocked?

What you've described is exactly how you find out you've been blocked. You know a page is there, but you can't see it or find it in search, and other users can confirm that it is there. That's how being blocked works.

Here are three tips of finding out if your friend has blocked you on Facebook:

1.)Ask mutual friends if the person whom you suspect has blocked you is still on their friends list. If they can view his or her profile, it is a sign that you have been blocked. Since you have already confirmed this, then yes, you have been blocked.

2.)Go through old conversations with that person. Click the 'Actions' button and select denunciar Conversation. If you see 'Blocked' seguinte to the person's name, this means that you have been blocked por the person. If you see 'Report' instead of 'Blocked' then it implies that the person has deactivated the account.

3.)Access the person's perfil link. If you get a "Page you requested was not found." it is either you were blocked or the account has been deactivated. Try to access the perfil link with a new account or another account to know for sure.

Source: link

Lucas Chad blocked me

Because when I look for my friend his perfil comes up with a blue square at it says This perfil is locked