Wells, Sump Pumps and Septic Sewage Systems - Seem to be losing pump prime

I have a cabin that uses a shallow well pump. Today we notice that the pump wasn't shutting off after it kicked on when we were using water. I switched the pump off with a switch that controls the power to the pump. I waited a few minutes and switched it back on. It took a few seconds but you could tell it picked up water and then the pressure switch kick it off and we seemed to be back in business. The same thing repeated off and on through the day. My brother-in-law felt the points were sticking in the pressure switch and ran a piece of fine sandpaper through them. When we turn it back on it ran, but a little later we were back to the pump running and no pressure and only a trickle of water. The pump seems to be losing its prime. If it were the switch wouldn't it pump water when the pump ran and ran? It sounds to me like the inline check valve may be letting water drain back down the well allowing the pump to lose its prime. I know nothing and just read some stuff today online. Any help would be appreciated.

You could actually be running out of water in the well. Many areas have experienced droughts in the last several years and the water tables have dropped considerably.

it seems to be losing pressure, at least as I understand your post, while it is running so any involved check valve should not cause this. If it were a check valve, it would pump to shut off but when it went to start again, it would have lost prime and needed time to prime. You seem to be describing a situation where you are losing water while it is running.