What does numbness in my right arm mean?

Nerve Problem: The nerve supplying that part of the arm is not working right. Could be due to pressure on the nerve, or injury or even more problem related to your body (systemic problem). Probably more info might be useful in finding the cause of it. I would suggest to see your doctor if the problem persists.

Nerve problem: Depends which part of the arm. Please see a doctor licensed in the US for examination and specific advice. Here is some general information about causes of arm numbness http://patient.info/health/numbnesspins-and-needles