Post-Surgery Irritation

I am a 31 year-old male who had stage 1 colon cancer 3 years ago.  I had an open section colectomy, which removed my ascending colon.  Since I was released from the hospital, I have had issues with inflammation, pain, discomfort, and blood at my rectum.  I have been checked by my family doctor and GI doctor.  Neither observed anything other than some redness and irritation--hemorrhoids have been ruled out.  I have been given suppositories, Proctofoam, and told to take fiber as possible solutions.  None have worked.  This is not an issue that I had before the colectomy.  Could it be possible that my body is not processing bile effectively? (There is sometimes an odor of bile that comes when I have a BM)  Or, could I have somehow acquired some kind of chronic yeast infection?  There is blood, at times, as well as a strong odor.