Quick Question Regarding A Drug Test. I Recently Went To

Quick question regarding a drug test. I recently went to a doctor for my migraines. She suggested a medication but told me I would have to take a drug test before being prescribed it. So I did. Today they called and said I tested positive for temazepam and that due to the postive result she will not prescribe me anything controlled in the future. I am an ER nurse and my husband is a police officer. We do not use drugs and this is very concerning for us. I have taken a low dose of Celexa for a few years but never any other drugs or benzos. Is there a potential for false-positives? What do I do now that this is on my permanent medical record. The doctor I saw I've never visited before and she was extremely unhelpful over the phone.