 [ Symptoms ] i found a little bit of blood in my stool could i have colorectal cancer [ Disease ] the earliest sign of colorectal cancer may be bleeding but if you find blood in your stool do not panic a number of different illnesses can cause bleeding not just colon cancer if you find blood in your stool see your doctor so that a correct diagnosis can be made and proper treatment received other symptoms to look out for if you suspect colon cancer include change in bowel habits constipation or diarrhea unusual stomach or gas pains very narrow stool a feeling that the bowel has not emptied completely after passing stool unexplained weight loss fatigue