I realize that the question was asked a while ago, but ... five days of taking catecholamine/serotonin affecting substances in a row is a sure way to fuck yourself up with minimum enjoyment. There is also a factor of having to drive back in the state of "suicidal Tuesday". Disclosure - I never understood the value of pot, if the idea is to dance while bonding with people - so that drug would not even under consideration. So in the spirit of harm reduction, if I were bent on attending a sunstance-requiring event of such a length, here is what I would do.
On day one (probably, the first night), I would take a lysergamide - if that is something that you enjoy under the circumstances. They are a lot better during a warm day on the beach than in a cold forest at night with porta-potties full of shit to the brim. Alternatively, you could take something in line of 4-Aco-DMT, but the same caution applies if you don't want to see shit crawling up your legs or feel suffocated by its smell.
If a lysergamide is not an option, I would take a triple releaser or a proper combination of such (MDMA, MDA, APB, APBDP, MAPB, etc.)
On day two, I would drink alcohol.
On day three I would take a dissociative of the type and dose, conductive to dancing and music appreciation, such as 2F-DK.
On day four, I would take a phenethylamine, whose action to a large extend is not affected by recent administration of triple releasers taken on day one, such as 2C-B or DOC.
On day five I would take BDO/GBH.
