I would definitely go to see your primary care doctor
or your OB GYN doctor about this issue. Three weeks of unexplained spotting is a long time, and it is worth getting some helping figuring out what might be going on.
The first thing your doctor will want to to do is perform a physical examination, including a pelvic examination. This will help them rule out some of the causes of spotting, such as a vaginal infection
, or an infection or ulcer on the cervix. Based on what they find with this initial examination, they may also want to get additional studies, such as basic blood work to look at things like the levels of thyroid hormone (which can cause irregular periods) as well as an ultrasound
to look at the anatomy of the uterus and ovaries.
If you continue to have this problem, then another cause that your doctor will want to consider is something called polycystic ovarian syndrome, which is one of the most common causes of irregular periods and spotting and which is more common in women who are overweight.
Start by making an appointment to be seen at your earliest convenience.