All of the above ..
Does the vehicle idle ok at a stop or does it idle down too low?Run rough at stops?
If it idles down to low where it acts like it wants to stall,then there could be an issue with the idle circuit and/or a driveability concern.
Either way,get this checked ASAP,dont continue to drive this until your sure oil pressure is ok.
You'll be sorry if it is mechanical
Have a technician check the oil pressure using a mechanical gauge hooked up to your engine.ASAP.