There is this guy at work that I am interested in. We talk occasionally and have flirted in the past. I sit in a high traffic area. I have noticed sometimes when he walks by me, he will put his hands in his pockets and slump his shoulders and look down. Other times, he will be humming as he walks past and making wild movements as if to get my attention. Why might he show this type of dejected body language as he passes by me? Is he not interested, or does he think I am not interested in him? Could I some how be the cause of these extreme behavior differences? I need help here cause his signals are all mixed up.