You can check your pins most easily by connecting the ones that you think are the power pins to a 5V supply and GND, and then connect the other one to a voltmeter. The voltage should change as you adjust the pot (or in this case, move your finger along it). If not, you've got the wrong pins. Change them and try again.
Do make certain (with the voltmeter) that you've really got 5V between the two leads of your power supply first.