chronic diffuse lower abd cramping

I am a 32 yr old female with no past medical history who has had intermittent lower abdominal pain for the past year.  It feels very menstrual-like, radiates to lower back.  Cannot find a pattern related to eating or bowel movements.  No diarrhea, occasional constipation.  Often accompanied by yellowish/white discharge.  Often bloated appearance but don't feel bloated.  Don't feel gassy. Went to PCP who said I was full of gas upon palpation.  Urine tested, put on antibiotics for UTI but symptoms persisting well after that treatment.  She referred me to my gyn who said exam and pap were normal, pelvic ultrasound normal.  Awaiting appt with GI specialist but that is not until 3/31.  Any thoughts?