I gave my friend urine to pass a drug test and it said she failed for opiates. i dont understand how when i dont do any kind of drugs at all.

False positives: There are other meds and a few food items that can cross react in the test and give a false positive. They may do a confirmatory test to check for specific opiate meds. However, that is despicable that you helped a friend pass a drug test by cheating rather than advising her to lay off any drugs since the test obviously was planned ahead of time.