At 733 (possibly 732 I don't think Diet Pepsi even has one calorie) you're dangerously under eating. Your body is not going to use fat as fuel with that little amount of food.
I highly suggest you up your calories to at least 1800 - 2000 calories a day, depending on your exercise levels.
You need to eat some more protein and healthy fat foods. Such as:
Chicken, turkey, more eggs or more fish throughout the day.
Also look at adding in some nuts for EFAs and possible cook your fish in olive oil. Look for other foods which contain essential fatty acids (omega 3 6 or 9 or all three).
Maybe add in some oats to your breakfast along with the good selection of fruits as a topping!
Well done with the water intake, keep it up! And apart from the low calories, you've made very good food choices!! Increase your calories and you will loose weight.