am a female, 18 years old. I have known how to masturbate since I was 13 years old. At first, I only felt it from the outside of my vagina, but when I was 14, I went to pee and saw that the color of my urine was more blood-colored. I thought it was my first period, but it wasn't until I was 15 that I started having my period. When I was 17, I tried to put my fingertip about 3cm into my vagina, but I couldn't feel if there was a hymen or not. So doctor, can you tell me if I bleed after masturbating, does my hymen break?

During sexual intercourse, some women experience heavy vaginal bleeding after intercourse, especially the first time. Many women experience this bleeding for several days. So what is the cause of bleeding for several days after the first time?