Water pressure suddenly has increased

Hi All. First off, thanks for any and all advice!  We have noticed an issue with our water pressure the last few weeks.  When the pump kicks on the water pressure greatly increases, (more than normal pressure) then a few seconds after it shuts off the pressure is normal again.  We are fairly new to living with a well.  3 years.  As mentioned, this is a recent development.  I have done some investigating and found out that there is no guage in the pit to verify pressure.  I did however check the pressure on the tank when the pump kicked off.  The reading was 48 psi.  The pressure switch is a 30-50.  I have been told to replace the pressure switch and nipple.  It just dont add up in my head that if the switch cuts out with 48 psi in the tank, it is doing its job. It has also been suggested that there may be an issue with freezing.  Temps have not been as cold as winters past where we had no issues.  Any advice and direction would be greatly appericiated!  Thanks!