How come I haven't lost any weight?

Without having access to your food diary I would suggest you check out

http://www.myfitnesspal.com/topics/show/872212-you-re-probably-eating-more-than-you-think

and

http://www.myfitnesspal.com/topics/show/1080242-a-guide-to-get-you-started-on-your-path-to-sexypants?hl=sexypants

And assess where you are.

Are you gaining weight? If you aren't losing anything and aren't gaining anything, you may want to reduce the number of calories even more. You could also do a little more for exercise to see if that works.

Normally, the calories in/calories out logic works. If you burn more calories than you take in, weight loss happens for you.

A pound of fat generally consists of 3500 calories. In a week, if you run a calorie deficit of 3500 calories you should burn a pound off.

Sometimes we may think a calorie deficit exists and we just aren't counting all of our calories or are exaggerating the amount we burn during exercise.

I guess my best advice is play with your numbers. Decrease intake or increase exercise and see if that works. Once you get a hold on how many calories you are burning and consuming per week weight loss will happen more quickly for you.

hard to say, your food diary is not open.