A 25-year-old executive assistant presents to the family pra…

A 25-year-old executive assistant presents to the family practice clinic because of a painful bulge in her vagina. The bulge initially appeared 3 days ago and has increased in size. She denies fever or chills. The patient is sexually active in a monogamous relationship. On physical examination, she has a tense, hot, tender circumscribed mass beneath the labia. There is erythema around a small opening. What is your most likely diagnosis?