Are Macbeth’s paranoia due to his own weakness or a consequence of what he did?

       Macbeth's paranoia is due to the consequences of what he did. He sees banquo right after he dies. That means that he feels guilty for killing his best friend. So from that point on macbeth paranoia won't let him live in peace.Macbeth paranoia won't let him  alone but that doesn't stop him from killing more people.