I had my period 2 weeks ago, but now i have brown discharge, i haven't had sex in at least 3 months and i'm not on any medication.

Many possible causes: Generally, a light brown vaginal discharge without any other symptoms can be associated with spotting from the uterus. A small amount of blood may reach the vagina through the cervix. Over time, this blood can combine with vaginal secretions and turn brown producing a brown discharge. If persistent or accompanied by other symptoms it needs to be evaluated clinically.