Valve cover mystery Knocking sound

[Skaterjunky8]

1991 DOHC KA24DE Fastback 5-speed

Ok I pulled over to the side of the road last tonight because my hood was up, and ofcourse my car is slammed and the shoulder had a dip as I went off at about 1-3 MPH I got stuck on the incline, it was pretty bad, sounded like my trans/motor hit the ground rather then the usual Power braces. So I reversed and pulled myself off the 'hump" turned my car off, hazards on, got out and pushed my hood down. Got back in, started her up and began driving off when I hear a strange knocking sound, look down at my guages and my check Oil light is on. Pulled over shut the car off, look under the car, nothing. check the dip stick, at the H mark. Oil cap has a slight gas smell to it, but other then that nothing was wrong. My motor still pulls like a champ, no sputtering. Changed oil 2 days ago, ran it at DS1, pretty hard i might add.

No previous engine problems, although if I sit in one place at idle for a while, then go to press in the gas, I get some white smoke, but I have to have been sitting for about atleast a minute. Someone suggested that the timing chain guide got lose and started rubbing the chain, but i dont see how that affects the oil light, uless I damaged the sensor by rubbing the motor on the ground.

Anyways (Sorry for the long story) but does anyone have suggestions, or things I should check to better figure out what might be wrong with my car