I think about 10lbs. Depends on your weight now. If you're a heavier weight, you will lose a lot more. But if you're borderline/underweight then maybe a bit less.

Height: 5'2"
HW: 80kgs (176lbs)
LW: 74kgs (163lbs)
CW: 74kgs (163lbs)
-GW1: 75kgs (165lbs)-
GW2: 70kgs (154lbs)
GW3: 65kgs (143lbs)
GW4: 60kgs (132lbs)
GW5: 55kgs (121lbs)
GW6: 50kgs (110lbs)
UGW: 45kgs (99lbs)

 

Hey, you're young. 14 years old. Before this goes spirling of control I want you to think and I mean really think if you want to be doing this 10, 20 years down the road. Once you start it is difficult to stop. Its like trying to stop a train in its tracks with a popsicle stick. Instead of feeding your ED by restricting to a very low caloric intake, make better decisions with your lifestyle. Cut out the junk food, become vegetarian or even vegan, do some exercises that you enjoy. Take care of yourself. You are young and still growing. Please talk to someone you trust so that they may support you.

 

At your current weight 122.5 with a BMI of 19.8 you could lose 5 pounds (it would require cutting back on 580 calories a day). Personally I would not recommend going that fast, the best way to lose weight is slow and steady. It prevents binges and helps stop your parents from noticing.

That being said you are only 14, during this time of your life it is essential to eat right so you have proper bone, organ, and brain development (it is going to be a very long, miserable life if development doesn't occur correctly). I would hold off from losing any more weight until you are 16 or 17.

Also as a side note for women a BMI in the 19s is typically regarded as the most attractive so if you are worried about fitting in or being prettier you are already in a good place when it comes to BMI.