I failed my drug test - why?

I've never even had a puff of a cigarette in my almost 20 years of living. I wasn't around anyone who was smoking pot and of course, didn't smoke anything myself. The day before I took the drug test, though, I was almost hospitalized for heat exhaustion, and threw up everything I had eaten that day. So when I took my drug test the next day, I only had a few crackers, water, and chicken broth in my system. Did I fail because they thought I was trying to flush out my body and not get caught? Thank you.