Then you should have a Hemoccult test, it's probably blood from the stomach. After that you should discuss with the doctor about adjusting of your anti-acid drugs. Even if H. pylori infection is cured, gastritis may persist and develop into ulcer from other causes (increased gastric acid secretion, aspirins, alcohol, acidic food etc).
it is spotted with black spots its not like balls.
Black threads or patches may be blood from gastric bleeding, probably from gastric ulcer.
Black pepper-like balls may be clumps of bacteria (overgrown normal or harmful ones) or candida.