Im 5,4 my scale says i weight 109 but why do my hip bones pop out slightly ? is it cuase muscle weights more t?

Muscles do not make hip bones stick out. Hip bones only stick out when you are thin. At 100 pounds at 5'4" you are horribly underweight. At 109 pounds you are still horribly underweight. Please see a doctor. You are playing with death! Nobody at your height should be that thin. Even at a normal weight your hip bones should stick out a little, but at your current weight, I sense that they stick out more than just a little.