School and Work: Open Question: Drug Test in a week. ?

I smoke pot maybe twice a year. One of those times was last Wednesday. 3 or 4 hits. Well out of the blue a new job opportunity has been presented to me. Probably will be taking a drug test by the end of this week or early next week. One of my friends says I'm screwed another says since I'm not a weed smoker I should be clean.

I am 32 170 pounds 5'11

What are my chances? What should I do?