Three children had bleeding in the colostomy 3 days ago. Now the bleeding is gone but there is pus and a big lump around the anus. The doctor asked me, is the colostomy bleeding dangerous?

I am currently in 11th grade and am very constipated. Now, every time I go to the toilet, it is often difficult and I can feel something. After normalizing, it retracts back in and is not palpable. So the doctor asked me or constipation with lumps in the anus when having a bowel movement, what is the disease?