I have a submersible pump that has lost pressure. It is reading 13 psi. The bladder tank is also not filling and the pump is not shutting off. Please help.

What's the PSI in the bladder tank when the pump's shut down and a cold water faucet opened up to bleed off pressure?
How old is your pump?
Let the pump get up to 13 PSI and then shut it off. Does the gage drop to zero? How far from the well head to your house? Back to you, Tom