If you dont hear anything by Friday, consider yourself passed. In the world of drug testing, no news means good news.
NEVER inquire about the test results! A clean person would never do this because, being clean, there is no reason to do so and asking for the results will only draw suspicion. You do want to be viewed as a "clean person", is that correct?

Just carry on with your job duties in the manner that a clean person would and stop worrying. You would be notified if there were any problems with the urine sample.