It is actually quite common for your weight to stabilize a bit after a large drop. My weight does the same thing-I might lose 2 pounds one week, 3 the next, 1 the next...and then go for a couple of weeks with no loss. The scale then starts dropping again.
First-weigh only once or twice a week. Give it another week at 1600 calories a day. See what happens. Try to take a look at the QUALITY of food that you are eating. You will get better results the better you eat-because 1600 calories of healthy food is utilized by your body better than 1600 calories of fast food or sweets. Make sense? Think of food as fuel.
Give it another week, and see if there is any loss. If you go another week or two without a loss, drop the calories SLIGHTLY to 1500 a day-and improve the quality of foods that you are eating. Let me know how it is going.