How to lose 4 pounds in one week?

I m 5'4 and 119 pounds and feel like it's too much for a small framed 19 year old girl. I ve been eating 1200 calories for a week and nothing's been happening. I'm still the same weight. I also try to do 30 minutes of cardio per day and am drinking more water than ever. I used to weigh 115 pounds a few weeks ago. What gives?
How to lose 4 pounds in one week?
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