What Blisters Near Vagina, Under The Arm And Under Breasts?

i HAVE WHAT LOOKS LIKE A BLISTER UNDER MY ARM THAT IS SOLID AND A COUPLE IN THE AREA OF MY VAGINA. WHAT CAUSES THESE. mY DOCTOR SAID THEY ARE HARMLESS, SOMETIMES COME WITH AGE BUT DIDN T GIVE ANY FURTHER EXPLANATION. i HAD A COUPLE UNDER MY BREAST SEVERAL YEARS AGO BUT THEY WERE MORE LIKE BLISTERS. A SPECIMEN WAS TAKEN AND THEY REPORTED i HAD SEPTIC ( CAN THINK OF THE CORRECT WORD) THAT YOU SOMETIMES GET WHEN YOU ARE IN THE HOSPITAL. I TOOK AN ANTIBIOTIC AND A TOPICAL OINTMENT AND THEY WENT AWAY.