bleeding for 15 days after sex

You need to go to your doctor as soon as possible. You may have an injury or infection. There are many possible reasons for bleeding during sex or bleeding that occurs after intercourse. But bleeding from the vagina either during or just after sexual intercourse is never normal and should always be checked by a doctor. The leading causes of bleeding associated with sex are: inflammation, atrophic vaginitis, sexually transmitted diseases, abnormal growths on the vagina, endometriosis. Some menopausal women bleed after sex because diminishing estrogen levels cause thinning of the vaginal walls, which can become irritated from intercourse. It is possible that you experienced some vaginal or vulvar (outside parts of the genitals) tearing during intercourse. When women have tearing around the entrance of the vagina, or just inside, healthcare providers sometimes prescribe specific antibiotic ointments in order to reduce the risk of developing an infection. Here's the site where you can find more information about it
https://www.steadyhealth.com/FAQs_Bleeding_during_intercourse_t146640.html