Thank you for your question.
Since you already had an ultrasound I'm assuming you are under the care of a competent gynaecologist. You will need a prescription for medication to control the bleeding and additional tests to determine the cause. The commonest reasons for uncontrolled bleeding with periods are anovulatory cycles,
thyroid dysfunction, other blood clotting related issues. Your gynaecologist needs to do a full work up to determine the cause and treat you accordingly.
Best wishes