That sounds more like the wire under the hood grounding out on something. Either that or it was about 3 quarts low (and not even show up on the dipstick) and you've toasted the engine.

An older engine with some bearing wear will eventually start flickering the light at idle, but it should go off when the rpm's rise. Any engine with low oil levels will first start to show the light on hard left corners as the oil sloshes away from the left mounted oil pump (racing Volvo's often have baffles in the oil pan to prevent this). There is nothing that I can think of that would happen with the oil pressure that would cause flickering at low rpm's, and a steady light at higher ones.