Hello, I can understand your concern. 50 years is the age when there are chances that you might be going through menopausal phase. Long and heavy menstrual cycles are indication of menopause at this age. Menopause means permanent end of menstruation cycles where production of female sex hormones significantly decreases. Hormonal imbalances are very usual during this phase causing long heavy menstrual cycles. You may need to consult your gynecologist and go for hormone replacement therapy during this phase to resolve the symptoms. There might be other reasons for the same symptoms like having uterine fibroid growths, inflammation of the uterine lining, infection of some female reproductive tract organ etc. However, all of these conditions are manageable. Long and heavy menstruation does take toll on the body that is manifested as weakness, lethargy and dizziness. Some psychological symptoms of menopause also include these symptoms. It is good that you already started on iron replacement therapy. Now you need to take proper nutritious diet and energy rich food. Take rest whenever you can. You might need to slow down for some time. Have plenty of water. I hope this information helps. Thank you for choosing HealthCareMagic. I wish you feel better soon. Best, Dr. Viraj Shah