An adolescent girl presented to the emergency department with a history of abdominal pain, dribbling, and inability to pass urine for the last 24 hours. The initial observations and examination of respiratory, cardiovascular, ears, nose, and throat (ENT), central nervous system (CNS) and musculoskeletal systems were normal. No onset of menses reported by the patient. She was found to have a palpable distended bladder on abdominal examination. A catheter was inserted by the nurse, who reported no abnormalities. The physician did not perform a FAST scan nor conduct a genital examination. The patient was referred to the paediatrics department and the following day an ultrasound examination led to a diagnosis of haematometrocolpos. The patient was the referred to the obstetric and gynaecological department. Corrective surgery was conducted the following day and she was discharged on the fourth day. While the diagnosis and treatment were correct, had a FAST scan and/or genital examination been part of the initial work-up, diagnosis would have been made in the emergency department and an appropriate referral made directly to obstetric and gynaecological team. Rapid diagnosis and treatment would have benefitted the patient, reduced the risks of complications, and cut the length of stay in the hospital by as much as two days.