Does Flushing The Body With Water Prevent Positive Results For Drug Test?

Hi There, I used cocaine, a very small amount (2 lines), last night, and today I found out I have to take a urine drug test by 3pm 6 days from now. Ive never done the drug before, I weigh 165 pounds, average fat and metabolism, and I m a 25 year old male. What are my odds of passing, and will working out/drinking a lot of water help to prevent a positive test. Thanks