I'm guessing the plastic thing the cows broke before was the cover on the pressure switch. If it was me I would look to see if the contacts are open or closed. Then I would check to see if there was voltage at the pressure switch, and if there is whether or not it is going through the contacts. (of course you'd need to be comfortable working with electricity and have a voltage meter).
It's possible you aren't getting power to the pressure switch ( broke wire, tripped breaker).
It's possible the contacts in the pressure switch are stuck open or are burnt. Usually you can see the contacts when you remove the cover and can tell by looking if they are open. If they appear closed but you aren't getting power through them then they are burnt. You may be able to clean them with fine sandpaper and get it going temporary but in either of these cases replacing the switch would be the right thing to do.
If you have power and the pressure switch is good that just leaves the pump itself and any wiring between the pressure switch and the pump.
Edit: There's also " pump is running but not pumping". This is more likely in an above ground pump than a submersible. Above ground pumps sometimes lose their prime and need to be primed. It also possible a foot valve stuck open, or there's a hole in one of the pipes (above ground jet pumps have two pipes going down into the well) or a broke impeller, or a piece of something clogging the jet .
