Well, in my opinion, it can be because you are scared by the ghost stories. Generally speaking, watery eyes can be caused by many reasons. For example, watery eyes can be a sign of dryness. As we know that tears are for lubrication and for keeping your eyes clean. So when your tear glands don't work in a wrong order, it may develop dry eye syndrome. In other words, if your eyes become dry and uncomfortable, the tear glands react by producing large amounts of tears. And it can be the most common reasons. But on the other hand, eye infection, allergies can also cause watery eyes. And for your situation, scary emotion which can just irritate your tear system can be another reason. And in my opinion, your eyes will be fine, after you have watched movie. So you do not need to worry about it.
