Reason For Itching Around The Private Parts?

I AM 54 YR OLD FEMALE, NOT MUCH SEXUAL ACTIVITY. LAST SEXUAL INTERCOURSE WAS PAINFUL. USED CONDON. DAYS LATER NOTICED DISCHARGE, THOUGHT PERHAPS STD. WENT TO GYNOCOLOGIST, PRESCRIBED METRONIDAZOLE VAGINAL GEL FOR 5 TREATMENTS. DR NOTICED DISCHARGE DURING VISIT. DID NOT THINK IT WAS STD. CULTURE TESTED GOOD. AFTER VAGINAL TREATMENT, DISCHARGE LESSENED BUT LINGERED. NO SMELL, NOT MUCOUS. ITCHING BECAME SERIOUS PROBLEM. SKIN AROUND ANUS AND HIGHER UP THE BUTT CRACK (sorry for lack of better description) became is still is RED. ITCHING IS SOMETIMES UNBEARABLE THEREFORE I SCRATCH WHICH RESULTS IN MINOR BLEEDING AND INCREASED WETNESS IN THE AREA. OUTER VAGINAL AREA ALSO ITCHES. I KNOW SCRATCHING IS NOT GOOD BUT I CAN T TAKE THE ITCHING. ITCHING INTENSIFIES WHEN I WIPE WITH TOILET PAPER AND I USE THAT OPPORTUNITY TO SCRATCH THE ITCH. ( BTW the toilet paper is clean) THIS IS GOING ON FOR SEVERAL MONTHS, WHILE I HOPE IT GOES AWAY. THE REDNESS OF SKIN AND INTENSE, AND I MEAN INTENSE ITCHING, IS MAKING ME CRAZY. I NEED SOME HELP. NOT SURE IF I SHOULD SEE DERMATOLOGIST, GYNO, WHO? Thank you for your time and would appreciate your advise.