Or he could have gotten gun shy after too many e-mails, too many questions, and negotiating a lower price than he was comfortable with.
Too many times lately, people have been buying watches and then immediately finding fault and trying to beat down the seller even further. I for one, would be very careful these days as to whom I was dealing with.
I have no idea what went on between you two and you may be totally above board. But it is possible that he decided against you as a buyer. Or not. Just something to think about.