What Causes Less Flow During Menstrual?

Hi there, I am a 14 year old girl and I have started my period two years back. My blood does not come from my vagina but it comes from the front. I am fat by the way. I eat normally and I eat vegetables. Right now I am on but nothing is coming out. If it does come out it's like a dot or two and I don't know whats going on. I am too embarressed to tell my mom or consult a doctor in person. Please help me. Thanks