The answer depends entirely on the threshold cutoffs and types of testing done. Urine screens done in office have levels/thresholds that give a positive or negative result. If your levels are above the testing cutoff then you will test positive. If below you will test negative.
Most in office screens are sent out for confirmatory testing using gas chromotography/mass spectrometry or immunoassay testing. Those tests look for specific metabolites of a substance, and whether the levels are within the expected range. If they are absent, too low or too high, the results reveal if someone is taking medications exactly as prescribed, trying to fudge results, or is taking too much.
The real question is are you taking your medications exactly as prescribed, running out early, and if so why.