You are a female and you stand at a height of five feet and three inches, therefore your "normal" weight should be 54.43-58.06 Kilograms or 120-128 pounds or 8 stone and 7.99 pounds. These weights along with your height when used in a BMI calculation put you in the healthy range with a Body Mass Index of 21.11. BMI calculators can be found on the Internet just by conducting a simple Google search for BMI calculator. Once you have found one, enter your height and weight and click calculate and the results will tell you what your BMI is and what category you are in. A BMI of under 18.5 is considered underweight and a BMI of 30 to 40 is considered to be obese. An ideal BMI number should be between 18.5 and 25.
However you should not just use the BMI calculation to determine if you are overweight because the BMI system has some great limitations. First of all, it does not take into account how much muscle you have (which as you probably know weighs more than fat). BMI is particularly inaccurate for younger people who are quite fit or athletic because they have a higher muscle mass which tends to make them overweight by BMI standards. Secondly, BMI does not take into account your frame size for example, you might be a perfectly healthy person with a large body frame but the BMI scale will class you as overweight. And finally, BMI does not account for any loss of height through aging which will cause the weight to increase without any consideration of height loss when getting older.