Missed periods

So guys, i need a little help. I recently started working out again after a few minths hiatus and currently in the 3rd week of burn 2. I'm also doing intermittent fasting (16:8) with the exercises. I eat pretty healthy with plenty of fresh veggies, meat, rice (I'm south asian). I always eat untill I'm full.

My problem is that my period is 4 days late. I'm freaking out because it's never been this late. I'm pretty regular. And there is no chance of pregnancy (I've not been intimate).

What should I do? Should I stop the fasting? Or should I eat more? Maybe add a hefty snack in between meals? I really don't want to stop exercising. It was hard to start again after slacking off for months.

Has anyone experianced this? What worked for you?

Update: whew! It started today. Thanks everyone for the support ❤️