Hi, I have read your question and I understand your concern. Anxiety, paranoia and the feeling of fear are very closely related to gastrointestinal conditions. They cause an increase in acid production, which leads to gastritis, GERD (reflux disease) and gastric ulcer. The black stool that you have noticed is coagulated blood coming from the ulcer in your stomach or duodenum (depending on where the ulcer may be located). There are very good treatments available for ulcerative disease or gastritis, such as Omeprazole 20 mg (taken once a day, for 4 weeks) combined with antibiotics against H.Pylori. But your main problem is anxiety and fear. Without treating it, every treatment for ulcer will be ineffective, cause they will reoccur. So, I would recommend you to : First, visit a psychiatrist or therapist. They will help you deal with anxiety, paranoia and any sense of fear you have. Second, see a Gastroenterologist (GI Doctor). He will order a fibrogastroscopy, to see the lesion in your stomach and guide you through the best treatments available. From what you have written me, this is not a case to worry about bowel cancer. The GI doctor will confirm this. I hope I have answered your question. Wish you good health.