Recent,while defecating,i bled a lot.i do not feel sore in the anus.symptoms occur a few days, then back off.what can i get sick? what should i care?

Must see physician: Rectal bleeding in a person age 24 is more likely due to bleeding internal hemorrhoids rather than colorectal cancer. However the incidence of colorectal cancer is increasing in your age group. You should see a physician for evaluation to be safe. It would be advantageous to be seen on a day when you are having bleeding, in which case a small scope will suggest if it's from hemorrhoids.