I feel a little uncomfortable in my stomach, back and waist, and there is a little black blood down there like menstruation, what kind of test should I do?

A little discomfort in the small stomach, back and waist, like menstruation below a little black blood, need to do human chorionic gonadotropin (HCG), ultrasound to diagnose whether ectopic pregnancy, gynecological inflammation, tumors and other causes.
1. Ectopic pregnancy: If you have had sex, missed your period or had a small amount of menstruation last time, you need to go to the hospital in time for a blood test for HCG, and then ultrasound to check the location of the gestational sac once the pregnancy is diagnosed to see if it is ectopic pregnancy that is causing the symptoms.
2. Gynecological inflammation and tumor: endometritis, salpingitis, pelvic inflammatory disease, uterine fibroids, adenomyosis, endometriosis, cervical cancer, etc. may cause the above symptoms, which need ultrasound, leukorrhea, cervical biopsy, cancer embryo test, etc. to confirm the diagnosis.
If the above symptoms occur, it is recommended to go to the hospital in time, complete the relevant examinations, and have the doctor formulate an individualized diagnosis and treatment plan according to the specific condition, so as to avoid delaying the condition.