A cup of cereal is under a hundred calories, and a cup of milk less than 200, so a bowl of cereal with milk should run about 2-300 calories. 500 calories is a Big Mac. Are you spooning sugar into it? Cream?
What the heck kind of sandwich has 1000 calories? Okay, a fully loaded footlong from Subway maybe, but you seriously have that for lunch? A normal sandwich, such as you might make at home, has 300-500 calories. No 6 inch sub has more than 600 calories. Why is your lunch the same size as your dinner?
1000 calories for dinner is more reasonable, but still - that's a huge dinner. That's like a generously large platter of spaghetti bolognese. I don't know how you could be hungry for that after downing an equivalent meal at lunchtime.
500 calories from drinks is truly horrifying because unless you're chugging milkshakes that's probably all high fructose corn syrup. A quarter of your recommended daily caloric intake, in the form of pure refined sugar! That's an express ticket to diabetes-ville right there. 4+ cans of coke daily is not a healthy intake.
I'm not trying to lay into you here. I'm glad you're experimenting with fasting. But, reality check - I would physically struggle to eat that quantity of food without being sick. I wonder if all that soda is messing with your appetite?