First, make sure the oil light comes on when you turn the ignition on (before you start) and goes out after you start it. If the ligh doesn't come on with the key on then you may want to pull the gauge cluster to change the bulb. Another check you can do, with the engine off but key on, go to the pass side of the engine and next to the oil filter is the oil sender (screwed into the block), pull the wire off the sender and ground it. Look to see if the oil light is on. you may just need a new sensor.

There is a manual adjustment you can do to the oil pump chain which may be the cause of the noise. There is an access cover down low on the front timing cover held on by two 10mm head bolts and behind that another 10mm head bolt for the chain guide. remove the cover, loosen the guide bolt and push the guide down onto the chain. tighten and replace everything and try again.