Drains in house are making a gurgling noise and pump in well seems to be running too long water pump is in the well about 75 ft down

The two problems aren't related. You have a blocked roof vent. Snake the roof vent that's closest to where you hear the gurgle.
As for your pump consumpion you may have a hidden leak or a faulty foot valve. Let's check and see,
Shut off the house at the house shut off and run the pump up to pressure and shut the power off, Watch the gage, If it falls you have a leak in the system in the well. Now open the house shut off. If the gage falls then the problem's in the house. Let me know what you find. Good luck, Tom

When I shut off the water in the house, about 15 to 20 sec. later there is a squeal noise you can hear throughout the house, especially loud in the master bedroom bathroom. It sounds like it's coming from the attic.

Any ideas?

Thank you,
Don

Hi donp and welcome to The Plumbing Page at ANHD.com.
Sounds like you have a valve or faucet that's developed a leak and what you hear is the pressure bleeding off, Try and pin point the noise. Good luck, Tom