What are some of the causes for a spot on my head that hurts when I touch it, like the pain radiates around my head, . No head trauma and no bump.?

Neuralgia. Some nerve endings exiting the skull are just under skin. These nerve endindings can get irritated and hurt upon contact/pressure from the outside. (occipital neuralgia). Infection in sinus and ear area can hurt as well as muscle tensions, skin lesions and even tick bite.
Unclear. It is very hard to help you with such limited information. I recommend that you start with your primary care doctor who can evaluate these areas and refer to a specialist if necessary. I hope this information is helpful. Stephen weber, M.D., f.A.C.S. Lone tree facial plastic surgeon.