If it feels like my colon is full still after i use the washroom, can that mean be normal? i heard of colon cancer, but stool seems normal. no pain.

May be normal: The reservoir of the large bowel is transverse colon and not rectum. One may not be fully emptying that site if having normal BM. The final solution is in colonoscopy where if nothing seen on complete scoping, this would rule out Ca. If such occurs the symptoms may be arising in small bowel and at that point TCT of abdomen would be helpful