Noob Questions + Helpful Tips/Tricks

So I’ve started my IF journey 2 days ago. I did the research and thought it could works well for me. I’ve started with the standard 16:8 and hope in the coming weeks I can transition into 18:4 and beyond. Something worth noting is I’ve also quit coffee as I started to notice it was making me feel ill and didn’t help perk me up.

For the record I am Male, 31 years old, 186cm/6’1 and 132kg/291lbs

So after the first few days I have noticed a couple of things that I’m hoping some seasoned veterans of IF might be able to help answer

1. The Headaches, when do they do away? Haha - I think this might be more coffee related but I’ve had a persistent headache from lunch on day 1.
2. Does a mineral supplement break my fast? - I gym of an evening between 7.30pm and 9pm - During this time I usually have 500ml of Vital All-in-one (https://www.vitaleveryday.com/vital-all-in-one/)
3. After my fast, I usually eat lunch around 12.30pm - Not long after I feel very warm like I’m running a temp, is this normal?

Finally, If there is any advice or helpful tips/trick you could provide for some just starting out that would be greatly appreciated. Tips on craving management, a replacement for coffee, music playlist, etc - Every little bit helps