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can cause some menstrual disturbance but incidentally you may having vaginal infection
which may have no other symptoms other than a brownish discharge called Bacterial vaginosis
. It would be best to get examined by a Gynaecologist to rule this out as it may be problematic later on especially if you plan on getting pregnant. Use condom only while having sex to avoid infection till you are diagnosed and treated. Since, there is some tissue coming out on urinating, there could be associated urinary tract infection
. Also do urine test to confirm. Drink plenty of water. Cranberry juice prevents against symptoms of urinaary tract infections.