Ship shaped aircraft hovering overhead that sounded like a drone but much louder.

There was a big ship shaped flying object hovering overhead. It was very loud and sounded like a drone, but bigger and louder. It had 1 or 2 white lights and 1 red light. It did not look like a plane or helicopter. It was moving very slowly in the same area for about 20 minutes, then flew away quickly. There were other what looked like smaller drones flying about as well toward the end.