A widely used tool to measure an healthy weight id the BMI (Body Mass Index). Usually, the BMI is only used for adults, but it can give you a good indication.
Here is how you evaluate your BMI: Weight (in Kg) divided by Height (in m, squared).
Or: Kg / (m x m). So in your case: 54 / (0,162 x 0,162) = 20,6.
Your BMI is 20,6 which is perfect.
Here is a table to understand what BMI numbers mean:
BMI <16 = Extremely thin (unhealthy weight)
BMI 16,1 to 18,5 = Very thin
BMI 18,6 to 24,9 = Normal (healthy weight)
BMI 25,0 to 29,9 = Overweight
BMI 30,0 to 39,9 = Obese (unhealthy weight)
BMI 40 + = Morbidly obese (many dangers to health)
So, right now your weight seems exactly where it should be. Congrats!