I fasted for over 3 days to start losing weight again

I'm pretty sure intermittent fasting is much more efficient than nonstop fasting when it comes to weight loss. I don't remember the exact details, but it was related to the fact that long fasting reduces your metabolism so much that the fat your body burns becomes very minimal, kinda like hibernation in animals. You should definitely read more about it though.

Are the multivitamins you're taking regulate by a federal agency? You'd be surprised at the shit they can put in there. Also, a vitamin doesn't have the bioavailability found in actual food. You should already have, for the most part, the proper vitamin stores in your body to sustain you through a weeklong or whatever fast. Electrolytes need to be replenished more often.
I would recommend the following: unflavored beef gelatin, dry scooped or in water (for protein to avoid muscle loss), calcium antacids (only take if stomach acid is bothering you), magnesium supplement, and maybe a no-sugar vitamin drink like Electromix (again, electrolytes.) Personally I also drink heated vegetable juice for the potassium and sodium content, but I have a hormonal imbalance that interferes with potassium so YMMV.
I think fasting is beneficial for a myriad of reasons, but do it right and know you still have to moderate your diet when you go off the fast. Obviously,don't harm yourself fasting, if everyday tasks get difficult because of exhaustion/fatigue stop!

its a bit early for ramadan

I knew someone that went without eating for days. They'd do this multiple times. She lost a decent amount of fat but she also lost muscle and despite the fact that she's skinny now, it's a saggy skinny. The bitch tried to ban my sister from wearing a tank top on my property. Don't be that person.

I don't know how people can go three days without food.

I can comfortably go an entire 24 hours without eating anything but surely after three days you'd be having some wicked pangs right?

Alpha GPC!!