Assuming you have experience with ecstasy- or MDMA-like drugs, you should know how you react to them regarding chronic hangovers. It can vary a lot and depend on expectations among other things. However if you have never tried this drug before, it is hard to say how you will react even if you can try to make some predictions.
How much experience do you have with meditation? If you have any, wouldn't you agree that during meditation your state of mind, current affairs in your head regarding emotion and thought, are amplified and manifested during meditation? If they surface, it is best to start off unencumbered so taking 6-APDB or 6-APB doesn't seem like a good plan.
If you can keep the dose limited and generally benefit emotionally from taking such drugs because for example they 'open' you then taking such drugs could be a good primer for a retreat, allowing you to make contact with yourself deeply.
So you see, there is certainly a considerable risk involved but it doesn't always have to pan out negatively.
Why did you put the D between brackets in the thread title? Are you not sure of the identity of the drug you have?