I am a 41 year old female, have had regular periods all my life. In the month of January I had two periods and I am still on the last one. The bleeding hasn't stopped, when should I go to the doctor?

Make an appointment. It could be due to perimenopause or it could be due to other possible reasons. Your doctor will likely perform an ultrasound to determine if a possible cause can be seen. It may be hormonal or it may be something such as uterine polyps which can be removed.