Been doing the right things so whats going on?

I have been eating reallly well lately, I saw a nutritionist and she helped me see how I can eat 1200 calories a day. So, I have been doing that, and exercising, and I haven't seen much weight loss so far. This is very disturbing because on my other program, where I drank shakes and ate protein bars, I lost weight very quickly. This program is a lot harder AND I am not seeing improvement. I actually have to eat right and exercise on this plan. I really hope I start dropping.