I was cut by unknown someone's blade do i have hiv /aids now please help me?

No risk, no worry: Exposure to sharps in the environment (used needles, someone's knife, etc) is listed as a possible risk for HIV, but in the 40 years of the worldwide HIV epidemic, there have been no reported cases of it actually happening except in health care providers caring for HIV+ patients. Any theoretical risk would require fresh, wet blood from an infected person easily visible on the knife.