Day 2 quitting Zyn after 1,5 cans of 12mg zyns per day för 4 years

Currently on day 2 of trying to quit Zyn after using them and other pouches for about 4 years. Been using at least 1 can per day, sometimes almost 2 cans per day (if drinking or going out) of the 12mg pouches.

Having a hard time with lots and lots of brain fog. Currently trying to study for 2 upcoming exams in the next coming 12 days.

Anyone got any tips for getting rid of the brain fog? And also how to stop thinking about just start using zyn again?