If things are a little hazy and you're not quite sure what's going on, you're in a state of confusion.
Confusion involves disorder, whether it's mixed up thoughts or plain old chaos. If everyone is screaming and running around, there's a lot of confusion. If you don't understand a math problem, you could be in a state of confusion. Mixing up two people who look alike is another type of confusion. If someone wants to make something very clear, they might say, "Let me clear up any confusion."