[Curls]

I agree that a medical checkup is always a good idea when there's a sudden behavioral change.

Another question is, has anything changed in his environment? New neighbors, a change in your daily routine, etc? Can you identify what's setting him off? Is it something new and different for him? For example, one of my dogs used to lose his mind when there were owls hooting outside. It wasn't a problem at all times of year, because the owls were only vocal during certain seasons. It wasn't normally a problem if the owls were out in the fields. The time that an owl was courting his sweetie from the tree outside our bedroom window though, yikes. None of us got much sleep for a few weeks there.