Don't quit yet. It's very natural to go through detox symptoms, as I'm sure you're aware, and they will likely be most prominent during the first few days. I immediately noticed on the first day that my sense of smell was heightened and smelling food everywhere made me even hungrier.
You're on day 5 (or 6 now?) I'm guessing that the worst is mostly gone, though I certainly can't predict your body's response. I had originally hoped to do 10 days. It had been nearly 20 years since I did such a long fast. In recent years the longest I did was about 3 days and that was rare. Recently I couldn't seem to get up the discipline to stay on a fast for a single day.
You've done 5 days and it's your first one! Start with congratulating yourself on that alone!
I will suggest something that may or may not apply. Years ago I was eating a lot of white flour, in semolina bread - a loaf a day - LOTS of pasta, etc. I decised to rrey giving up wheat. I don't even remember why but I was realizing that I had certain sensitivities to food and wheat is the most common food allergen. Well, about 4 days into a wheat-free diet (not even fasting, mind you) I was thoroughly depressed feeling nearly flu-like. But after that I felt a surge of energy that was terrific. Though I've continued to eat wheat it's been very rare that I do.
You may be having that kind of reaction, either to having no white flour products yourself or from withdrawal from anything else.
Although I had detox symptoms for a while on this fast, at several periods, the hunger did go away fairly early. After that I mostly had to wrestle with thoughts of food and missing certain things - or looking forward to them - rather than actual hunger.
Stay the course. Congratulate yourself for how far you've already gotten.