Jennifer prefers pools over the ocean because almost every time she goes to the beach, there’s a shark sighting. Now this. She’ll never go in the ocean again!   A guy on the 16th floor of a Panama City Beach hotel filmed a hammerhead shark making a beeline for a man standing in shallow water . . . and then turning away at the last second.   You can also hear people on shore trying to warn the man.  A biologist says the way the sun hits the clear water makes it hard to see a shark even when it’s right next to you, and this kind of thing is much more common than people probably realize.