If the pressure switch was bad and the pump continued to pump it would bog the pump down against the system pressure.
If the pumps continues to run the diaphragm may be leaking back and not allowing the pressure switch to reach cutoff or you are pumping water somewhere, major leak.
I am assuming you do not have an older demand system where the pump maintains a pressure head on the air above the water line in the tank. If that is the case and there in very little water in the tank the pump will run for a long time before it can build pressure in the tank.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles