I have a numbness in my right ear, what could this be?

Many causes. How long it last?How frequent?With headache---causes include local causes, neuropathy, migraine, cervical pathology--need complete history.
Could be the jaw. The numbness you feel could be around your ear and not your actual ear. Sometimes jaw spasm or jaw joint symptoms can lead to the feeling of numbness. Check with your doctor or see an ENT specialist for an evaluation.