Need some advice here... My first day on the road to a healthier me made me sick. By 11am I had a raging head ache, by 4pm I was vomiting (if I lost my lunch can i subtract those calories???

). Before starting this diet I was consuming about 3600 calories a day <cringe>, so I cut it in half. I didnt do anything stupid like cutting out caffeine, I still had my normal two cups of coffee with breakfast. For breakfast I actually ate more than normal, usually I just have a banana or two pieces of toast and then have lunch early ( breakfast at 7am and lunch at 11). I ate more for breakfast then tried pushing lunch back til 2pm, with a snack in the middle.
I guess what I'm wondering is if anyone else has had this problem and what they did to resolve it. What I'm considering is front loading my meal plan, eating more for breakfast and not pushing lunch back so far. Then eating lighter for dinner. I did stick to the calorie part but exercise is totally out of the question now considering how I feel.