Pressure drops to zero

I have a submersible well pump connected to my 40 gallon bladder tank that is set to 30-50psi. After using a large amount of water (a few volumes of the bladder tank), my pressure drops to zero and I dont have any water. It seems as if my pump shuts off. The contacts on the pressure switch are connected (sending power to the pump), but I am not getting any water. Is this because my pump is overheating? Do they automatically shut off? Am I draining my well dry? I don't know what kind of pump is in my well, but I do know that it is a 4" casing coming out of the ground.

Any help is appreciated, thanks.

I'm thinking that you are drawing the well down too low. You could check the amp draw to see if the pump is on, but not getting water to the surface. At least you would know whether the pump[ is shutting down or not.
If overdrawing the well is a problem, you may want to investigate the possibility of using the well pump to supply a storage tank, then another pump to pressurize the house system.
Ron