Hi there OP! I want to give you a warm welcome both to our community and to the world of poly-substance abuse. I never had a quinciniera, but I certainly had someone shoot me up the first time I got super high on Opioids and Benzos and they're pretty similar.'
All jokes aside, this is serious business and I'm happy to say that you're approaching it with a reasonable amount of caution. You're treading into unkown territory and good on you for wanting to arm yourself with knowledge.
Benzodiazepines are known for their propensity to produce what is known as a BLACKOUT. That is, a moment in which you're often still functioning (say, driving a car) but are indeed no truly conscious for the experience. It is similar to Alcohol in this way both chemically and socially. The more you take, the more likely you are too end up blacking out.
Now, when combining Benzodiazepines with other Centran Nervous System Depressants you are adding to the possiblity of blackout in simple terms, but in more complex terms, combined depressants from different classes have a tendency to produce sedation and such at a level greater than any of the two drugs would cause on their own. In short, the sum of the equation often becomes more than the parts that the equation would imply.
So, it is always best to use good judgement and be as safe as possible. You are doing so and as you are in the care of a physician who deems you to be an acceptable candidate for such treatment, I'm inclined to say, "have at it dude". Like anything new, tread carefully and pay attention to how the drugs effects you. Try to put this knowledge away for later use like a library book. Next time you have such an experience and say, the doses are not exactly the same, you have a reference point from which to proceed. In short, you're better off with the knowledge.
Go ahead and experiment and see how you feel. Make sure you are lucid for the entire experience and if you feel truly inebriated by the cocktail then you should regroup for a variety of reasons.
1. You could hurt yourself in an inebriated state
2. You are using these drugs primarily to treat a very real condition that you may have for some time. Part of making Opioids and Benzodiazepines work in the long-term is by using the lowest doages tolerable and only increasing when you feel it is truly necessary to do so in the context of your condition.
If you start using your meds to get fucked up, your tolerance will increase more quickly and the medicines will ultimately lose their benefit at a faster rate than had you used them responsibly.
I hope this helps.