Are you sure your fingers aren't in there?
Otherwise, the flash could just be misaimed or mistimed (not synchonized with the shutter. What I would do is bring a pic to a ma and pa camera shop and ask them what it is.
You could also take a pic of you to see if you notice the lack of light at the top half of the pic (like if the flash is pointing down).
Are you zooming in in that pic? Because sometimes the zoom has a further range than the flash...