They Said I Failed A Drug Screen Today. I Take

They said I failed a drug screen today. I take metformin HCL ER. promethazine, Diazepam, Naproxin, Topiramate, and Amitriptyline. I've been sick with a chest and head cold. My Dr. prescribed me Levoflaxin. I have also been taking Robitusin DM and Alka Seltzer Coid and flu. I take zantec every night for acid reflux. I tested pos. for methamphetamine and amphetamine. I know I haven't done anything like that. Can you exsplain That for me?