Ask. When I defecate, when I push or do heavy work, there is a shadow below the anus. When it returns to normal, it drops back in. What disease is this? How is the treatment?

Hi doctor. I am female, 20 years old this year. From the past 2-3 years I have had digestive problems. Specifically, I rarely feel the urge to defecate, so I often have to go to the toilet to push, but most of the time I can't. On average, it takes about 3-4 days to have a bowel movement, sometimes once a week, solid stools, no blood. I still eat enough meals, eat enough vegetables, enough meat, fruits, drink yogurt and exercise regularly. I also never had abdominal pain, belching or diarrhea. In short, all of my activities and health are very stable and normal, the only thing is that I don't feel sad to have a bowel movement and it's very difficult when I do. I tried visiting a few places but they couldn't conclude exactly what the disease was, and after taking the medicine, it didn't work. I want to ask if it's difficult to defecate, only once every 3-4 days, what is the reason for having solid stools without blood so that I can have an early diagnosis and treatment. Thank you!