Question: what does it mean when a guy looks at you and shakes his head?
Answer: Frowning and shaking the head “no” are two unmistakable signs of closing down, but many people are too polite to use such obvious gestures. ... In that case, you want to watch for the position of his head. If he is moving his head and body away from you, even slightly, that may be a sign that he is closing down.