Most pregnancy tests are not too accurate until about three days after period due date so it is very possible that you could be pregnant. Your doctor can run a blood test which is more accurate.

Also although most nipple discharge is normal, especially in pregnancy or other hormonal changes, there is a possibility of infection so as the colour is brownish, I would also want the doctor to rule out other problems. So I am afraid that you should see your family doctor to confirm both the issues.

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Brown discharge could indicate the presence of blood in the milk, this could be from the lining of a damaged duct. This damage can be due to infection or the presence of a papilloma (a wart like growth). Thyroid problems can be related to discharge or even the possibility of trauma from falls, or chronic stimulation from too regular self examination, or intense sexual activity.

Other causes of discharge can be due to hormone or pituitary problems. There are other conditions such as fibrosis or duct damage that are more likely to occur older women.

As you can see there is quite a list, it is very likely that it is related to pregnancy especially given your age but you need to have that confirmed by a practitioner.

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