This is a severe case of peptic ulcers, as you may know the black stools are from the internal bleeding
caused by the ulcers, blood turns black during digestion and has a characteristic smell, the blood loss has weaken your defenses hence the fatigue
. Treatment for H.pylori is with antibiotics but since your stomach is ulcerated I would suggest you seek an injectable antibiotic therapy that way your stomach wont suffer from the irritation from the medicine, also prevent eating irritating or spicy foods, drink plenty of Maalox
to reduce acid in the stomach and if pain persist eat some CHUNKED ICE (cold
food help reduce the bleeding). I understand your allergic to some antibiotics but its mandatory to find one that you can tolerate since it's the only way to kill H.pylori (which is the bug that make your stomach make more acid).