I get the world's absolute worst period pains when I'm on my period. Quite often it hurts so much I have to throw up. Am I ill?

No, but it sounds as though you have severe period pains. Your hormones affect the contractions in your uterus, which can be so severe that you throw up. It’s not dangerous. Rest, heat, exercise, painkilling tablets, acupuncture, a healthy diet and omega 3 (found in oily fish) can all help ease the pain. Ask your school nurse, your GP or a young person’s clinic for help if it all gets to be too much for you.