Failed False Negative UA what are my options?

Okay I explained a bit of my problem in a previous post but have been doing a lot of research and understand a bit more now so my question is.... If you have a (what I KNOW to be impossible) false positive Urine test what are your options? I KNOW I took my meds the day before however I was told to be fasting for bloodwork and since I have to eat something with the Vicodin and muscle relaxant I take at bedtime I skipped this dose the night before. I also did not take any of my vitamins, tramadol or Advil the next morning for the same reason since I was told to ingest nothing. I told the doctor this but now get the feeling they didn't listen. I was in fact so dehydrated by time the got around to taking blood they had a hard time getting any and getting enough urine for a sample wasn't easy either. Needless to say I was hurting real bad by this time but took nothing as directed until after my appt. I have now been told I cannot get ANY pain meds from this doctor since she says the test showed I had none in my system. How this is possible I do not know since except for fasting as ordered I've been taking the pain meds for years. I was worried it would come back I was taking too much since I had a bad episode the week before not come back that I am taking NOTHING. Now I know you all don't know me same as the doctor since I just moved to the area but I am being 100% honest. I feel like a criminal and after doing some reading here am wondering if I will ever be able to find a doctor to manage my pain NOW? Will I be red flagged and refused treatment because of one test I know in my soul is wrong. Doctor refused to even discuss it and left the room and got the practice office manager who basically told me I had no recourse and to leave. On top of all this I am on Cobra coverage and lose my insurance the end of the month so I don't have time to establish a relationship with a new doctor even if I could get an appt. I've already been refused coverage with other health insurance companies because of my back surgeries so will have no insurance in just a few weeks. Will this failed test also mean I can't get into the Pre-existing condition pool in my state in 6 months? I have to wait that long before even trying to apply but now am wondering if this test will prevent me from even getting that. I have read on here that others have had a false negative so am hoping maybe someone can give me some pointers on what to do and how to go about proving I am not a criminal or liar.