Is it normal that i slack off when the most important exam of my student life

Lol eating nutella like a boss lol????
if you stress ur self with all that studying you'll forget all Your material give it a week or two of studying before the test.

Just commit to being focused. I offer myself rewards for studying, like: read this chapter, get a snack. Study for this amount of time, watch a half hour of tv. Breaks are actually really important. Oh, and another big thing for me is showering. When I start feeling really antsy, like I can't study anymore, I shower. It makes you feel refreshed and you can start again.

But just so you know, studying can actually be ineffective if you're not committed to it.

It's not too late. Just sit down and start revising. The hardest step is the first but you'll soon get into it.

Sit down and start!!!