Capsicums (red peppers) have about 3 times the amount of vitamin C as oranges. Kiwi fruits have more Vitamin C than oranges. You only really get any Vitamin A from carrots if they are cooked (Vitamin A is beta carotene). So if you are going to have them, cook them. Green vegetables like beans and broccoli are good for energy (Vit B), and dark green leafy vegetables are even better.
Legumes are great for Vit B also.
Other than fruits and veges, incorporate some nut fats in there, like almonds, walnuts, and sunflower seeds. And just an extra piece of info, raw fish like smoked salmon/trout are the best way for your body to absorb good quality omega-3 fats. They get destrpyed during heating, and are not really even worth eating (for their omega fat value) after that. Just thought it was an interesting thing to know.
Vitamin B's, Vitamin C's and fats should help you feel a bit better.
B, the caffeine is giving you a quick energy high than leaving you crashing. Try protein shakes, exercise, and high energy foods like eggs, salmon, blueberries, sunflower seeds, yogurt and dairy,water is best.