Might be counterintuitive, but have you tried it without supplements (except electrolytes as needed)? Once I started fasting I realized that often things like multivitamins make me feel crappy; my theory is it’s because a lot of nutrients are used to metabolize fats, proteins, and carbohydrates and it throws things off balance to have the micronutrients without macronutrients.
My day 4 felt like what everyone describes as day 3. I’m on day 5 now just starting so not sure what it will be like today. I’m no help here except to agree with you that it doesn’t always get easier like others describe. I decided that even if it doesn’t feel great, I’ll keep going to 7 just to see ( unless I’ll actually ill).
I don’t see why you have to go beyond day 5, or even that far. There are really great benefits to fasting every other day or doing 2 days spaced out over 5. I do mostly 48 hour fasts and I’m really happy with that.
When do you start your fasts? I start on Monday because I know I’m not going into the weekend. It’s so much easier at work because I am distracted by work and I don’t have access to my pantry. I’m also kinda cheap so I don’t want to walk across the street and spend $7-$10 for lunch. Maybe if you started your fast on a Saturday and get through Day 1 & 2 on the weekend, it will be easier for you to continue throughout the week.