I am having large blood clots and extreme bleeding. Is this normal for a 16 year old female?

No. You should consult a gynecologist. You should start taking oral iron and multivitamin supplements to prevent iron deficiency anemia. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex. Get HPV vaccine.