Ive had mine come on for 2 reasons. Oil level was low (was actually the case) or the sensor was going bad (oil level was fine but some crude or something messed it up, some engine clean product from liquid moly fixed that with a fresh oil change).

When I had to much oil in the car the warning light in the middle of the odometer came on and that one will beep at you.

Either way, just monitor your oil level.