Hey
@Josephine_Morphine 
Welcome to the forums!
I'd definitely encourage you to read over our guidelines before posting. We're not wicked harsh about enforcement, but we try our best to keep a semblance of order here and we ask people to do their best to help us with that.
We don't typically handle threads dedicated solely to drug testing questions. There are a couple of reasons why this is. Mostly, it is because these are usually questions which we cannot realistically answer remotely. Secondly, these questions are often in the context of serious, life-altering consequences and we do not feel it is ethical to tell people one way or another, potentially instilling false hope or fear in the process.
I will throw you a small bone though before closing this. Yes, your experience with Diazepam (Valium) is pretty normal. It's the bane of drug tests for this reason. For instance, at the Methadone Clinic, policy has long been to cut a person's dose in half immediately when they pop for Benzodiazepines and to only set it back following a negative test. This has led to a lot of bullshit for a lot of people, many of whom, like you, only took a single dose of Diazepam and are still paying the price weeks later.
I have had Diazepam pop past 3 weeks and in my experience, it never was gone prior to the 2 week mark even in the best of circumstances. The good news is that it should be gone any day now. I would advise you to do all of the regular stuff like drinking plenty of fluids like Cranberry Juice, though this doesn't have a major impact on the speed of your metabolism, though it will help.
In the future, Benzodiazepines like Lorazepam (Ativan) and Alprazolam (Xanax) are known for being out of one's system at a faster rate. Clonazepam (Klonopin) is a bit of an odd duck in my experience. I've had it make me pop for two weeks before. I've also taken it before and gone to piss the next day and been totally clean. I'll add that both of these outcomes have happened multiple times with Clonazepam, so I tell people it's best to treat it as a similar thing to Diazepam.
And definitely, definitely stay away from the Chlordiazepoxide (Librium). This guy has to be metabolized into Diazepam as a step in its metabolic pathway, then the Diazepam starts getting broken down. It's not uncommon for people to pop a month after their last Chlordiazepoxide dose.
