6yrs ago i had sharp pain ovary for 1-2minutes w/brown&thick discharge.no periodpain&ultrasound has never showed cysts other than pco. endomistriose?

That's possible...: The differential diagnosis for pelvic pain is long. If it was acute in onset, it could represent something benign like a ruptured follicle or something severe and ovary threatening like ovarian torsion. Vaginal discharge also has many possible causes. If you experience the symptoms again, i would seek care at a doctor's office or in the emergency department.