Day Four & Five - Sticking to it

Trying to cut back on calories and eat every 2-3 is grueling! yet all in all, I've been doing fairly well. I've cut back drastically on soda, limiting myself to just one per day - which has resulted in horrible caffeine headaches. I've also been averaging about 1000 calories a day. It's yogurt, then cheese, then grapes, then yogurt, then a dinner of fish, veggies and a tad bit of rice.
Since the 1st I've lost 5 lbs. but I'm sure once the water weight catches up with me the scale will go up a bit. I've been drinking so much water I feel like a fish! The only thing I haven't yet done is commit myself to an exercise regimen. I figure first I need to get the diet down as second nature, then I'll start on walking an hour a day - especially since I just finished radiation today and will have more time to do this weekly, cause once I start chemo later this month I should only have to go every other week.
So fingers crossed that the scale keeps going down - and that the headaches ease up soon....it would be so easier if I could tolerate diet soda!