As one writer put it:

Do you ever find yourself trudging along as if in a fog? Something's off and you can't nail it down. You're swimming through mud, and nothing makes sense. Finally, the light bulb goes off in your mind; you're under spiritual attack.

Stuff is going on in the unseen realm, and it's affecting you. The cloak of darkness over your mind is a common symptom of the fog of war. If you don't recognize it for what it is, the attack may take you down. Where and when have you been spiritually attacked? What are the warning signs that you've been messed with by the Enemy?