Causing harm to others is forbidden; one who does so bears as much of sin as he has committed. It is also prohibited to hire a sorcerer to harm a person, and the work of that sorcerer is considered Kufr (disbelief), as Allah says (what means):
...but neither of these two (angels) taught anyone (such things) till they had said, “We are only for trial, so disbelieve not (by learning this magic from us).” And from these (angels) people learn that by which they cause separation between man and his wife, but they could not thus harm anyone except by Allâh’s Leave.
(Surah Al-Baqarah, 2: 102). You should repent to Allah and seek His forgiveness. Never again go to a sorcerer and do not harm others. Both are gravely sinful, the sorcerer and the person who hired him.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.