Its a long story but..............

If the oil level went just up to the tip of the dip stick @ its lowist point would that have mucked my engine up wasn't run for long may be 20 mins of driving cam is slight tapin from cold but goes away after a few mins of driving

 

Did the oil W/L come on at all,if it did not it should be ok;the top end tapping is that just since you ran it low on oil or has it been doing that for some time?