Check Oil Light on after oil change.

My check oil light came on and I went and had my oil changed. The guy told me my light might stay on and flicker. Which it does. I looked online on how to reset it. There was one way that said you need to with the ignition turned but not on press on gas pedal 5 times in 10 seconds then hold it down for 10 seconds once it blinks off then do it again for 10 seconds then turn off for 3 minutes. Which I did and it didn't work. Then I read about the self diagnosis reset. So I removed the panel next to the gas pedal turned it clockwise all the way then turned it back counter clockwise all the way. This didn't reset it either. Did I do it wrong? I don't know too much about cars either so I apologize. It said to turn it back all the way counter clockwise which I assume means turn it counter clockwise till it stops? Right? Please help. I don't know why the mechanic didn't just reset it for me.