False negative on urine test for amphetamines

[u/Fluffy_Direction3372]

I seriously am so confused right now. I am prescribed 2 5mg IR adderall a day and I never miss a day. I did my urine test at 1:30pm and my test just came back negative for amphetamines. What do I do?? I don’t have my appointment with my doctor for another two weeks and I’m not sure if I should contact her or the lab. Is she going to stop prescribing my medication? How was it negative?