So you never tried ALA and DMSA, but you expect to crash. This is only speculation.
I promise you that NB alone will not help you if mercury is an issue with you. Even when the body gets stronger through NB and tries to dump some mercury you would likely not get this mercury floating around without a binding chelation agent. It will only delay the process if this will be the case because it will destroy all the process from NB by serverly damaging the thyroid and adrenals.
Besides this how will you detox the brain and CNS from mercury without ALA. Mercury's halflife in the brain is more then 25 years. If mercury sits inside the hypothalamus no NB protocoll will get your adrenals and thyroid to work...