What am I doing wrong?excersise help?

Hi I found out I weigh 153 I don;t like that weight I am 5'1 and a half. But the way I am shaped it doesn;t look like I weigh as much as I do or that I am big but I know I am considered overweight I eat 1200 calories a day drink 6 bottles of water I do workouts of Biggest Loser and Jillian Micheal dvd's for excersise I try to do 30 mins to an hour a day. But I am still gaining weight.. Can someone tell me what I am doing wrong? Is it the water that is bloating me up.. Your help would be much appreciated.