I have a burning pain on my hand, arm, and scalp without a rash. it hurt very bad just to touch those affected areas. what can this be?

Inflammation: If the affected areas are all connected on the same side of the body and if rash develops within a few days ---could be shingles.

Nerve pain: This could be multiple things however two things that comes to mind are pinched/irritated cervical nerves or less likely, multidermatomal zoster without the rash. An examination would be helpful.