He took annoyance in you not taking the bait. You did not take the paper with a scribble about him, despite you either realizing about the danger of that, or discarding it as an internet prank. Now he's onto you. What happens next will depend on what you do or not. But for now, watch your back. You can already feel an ominous supernatural feeling of being watched from afar, you just can't figure out where it is from.