1200 calories is more than doable my friend.
Remember, you'll lose weight if you burn off more calories than you consume. You're always burning calories (sitting at the computer, taking a shower, etc..) but to accelerate this you need to exercise. Go to the gym or go for a run, the weather is perfect for a nice jog around the block. Make sure you eat lots of fruit and veg and stay away from sugary foods. That's what method I used to lose weight. I was 5 ft 3 and 63 KG. Now at 56KG