Plz help with well x trol wx-202 low water pressure

I have a well x trol wx-202, I have water but its very low water pressure. The pump cuts on at 30 psi and shuts off at about 60 psi, when I first turn on the faucet it has great pressure for about 20 seconds then it just goes to a slow trickle. I did shut the pump off and let it drain completely then turned it back on it filled up quickly so its not the well, but still the pressure is slow. Someone told me that I should put some air in the tank with an air compressor, is this the right way to fix my problem and if i do need to put air in the tank, how do i do it. should it be empty when I do or full and how much should I put in????

I just found a post about how to check the air so I'm doing that now to see if that is the problem, and I'm going to check the switch as well to see if its 30 and 50, instead of 30 and 60 because it looks like its supposed to be a 20 diff not 30. So I'm going to check the air and the switch, but still if anyone has any advice I would greatly appreciate it. Thanks in advance.....

yep, only has 15psi when empty, so I'm going to find a air compressor and get it up to 30psi and see if that fixes it... I will post if it does!!!! :->

Pressure switches come factory set at 20/40 30/50 and 40/60
Your tank pressure needs to be 2lbs less than the cut in pressure.
A 30 lb swing is ok but you will get a more noticeable drop near cut in pressure.

You may also want to check your tank to see if it is bad, you can do this by draining the tank and then shaking it to see if there is any water in it. If you hear water in it this would be your problem. I say this because your tank should not have 15 lbs in it unless someone let the air out. The tanks come from the factory with about 40 lbs in them. If there is no water in the tank then put some air into it and check it periodically to see if it is losing air, if so then it is your tank. As Wally said you need to ensure the pressure is atleast 2 pounds less the cut on pressure. You also don't want to trust your pressure gauge, you can check your pressure more accurately by using your tire gauge. When the pump shuts off check the pressure immediately and when it cuts on check it immediately and the pressures you get are the correct ones.