Please help me !????

First of all, stop the throwing up. You are a slim, young man who should weigh about 120 - 130 lbs. At your age and height you are a little under weight. Eat properly and eat nourishing food. Many boys your age eat a lot and don't gain weight because they burn off the food by physical exercises. You have 5-6 years of growth left in your life. You might grow to your father's height or in between. Eat healthy and thrive. Incidentally, water weighs about 7 lbs per gallon. If you drink lots of water or fluid like milk your body will show it on the scale until the next morning. Take care and good luck.