The smear they did that shows bacilli and white cells actually sounds pretty normal for the stool. The "pus" cells are white blood cells. Usually, when you have a "bad" bacteria or pathogen you would a lot more that 6-8. Bacilli are normal in the feces. Did they say if they were "gram positive or gram negative." So in order to tell if you have an infection you have to get a stool culture not just a smear or gram stain (which is what they did). Diarrhea can be caused by a lot of things so I wouldn't worry about cancer. Since you have a ulcer are you being treated with several antibiotics for it? If so you could have developed Clostridium difficile toxin, diarrhea. It causes bad diarrhea (about 10 times a day). This has to be tested for specially. So you would have to ask for it. They have to collect it in a particular way. This can happen after taking several antibiotics. You carry the Clostridium difficile in your intestines and it doesn't cause a problem until you disrupt the normal intestinal flora with antibiotics. It is really worth getting checked out.
If that isn't it then it could be a lot of things. Have you been eating anything new lately that would cause a food allergy? Did you eat out or travel? I also read that Ulcer medicines can cause mucus in the stool so that could be the reason for this. Also irritable bowel and Crohns disease will cause mucus if it persists. But I think that isn't the case. Let me know if you have any questions. Also, how it goes.
Have you been checked by a doctor to see if you might have Crohn's disease? To be more specific Ulcerative colitis. From what you are describing, that is what it sounds like you are experiencing to me. It might be something you should look into.
Hope you get feeling better.