scared- tested positive for benzodiazepines

I'm 7 weeks pregnant and had my first appt this past Monday. Called today said I tested positive for benzos. I'm freaking out. I took Valium in AUGUST when my dad was in the hospital. It's mid October!!!! Wtf!!! How long does that crap stay in your system?!? I go back in 4 weeks to re-test. Lady made me feel like a criminal. Said they would have to investigate if I'm positive again....? My mind cannot comprehend this. When will this medicine be gone!!!?!