<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, Ive been having a really heavy menstrual flow and experiencing a lot of premenstrual tension and irritability lately. Do you know what could be causing this?  <response>: It sounds like you may be experiencing premenstrual tension syndrome. This is a common condition that affects many women and is caused by hormonal changes that occur during the menstrual cycle. 