The presence of dribbling menstruation in a 13-year-old girl may be a manifestation of pubertal dysmenorrhea. The girl is relatively young, the ovarian gonadal axis is not yet well developed, and the ovarian ovulation function will be irregular. It may be due to the prolonged absence of ovulation, a single estrogen stimulates the endometrial hyperplasia and leads to dribbling menstruation. You need to go to the hospital for abdominal ultrasound to see if there is any organic disease in the uterine adnexa, and also to see the specific thickness of the endometrium. Due to the prolonged bleeding, blood tests should also be done to see if there is any infection and anemia. If there is no infection or anemia, and the thickness of the lining is less than 5mm, you can take Uterine Hematoxylin and Yunnan Baiyao for symptomatic treatment.