I've read headaches are rarely caused by brain tumors, but when they are, are sharp, short-lived and random pains,or dull and constant pain?since yesterday,sharp pain comes and goes on right side of head but then disappers.sound like type with tumor?

Only if a person...: If a person is a scientist researching brain tumors, or is a patient recovering from recent brain tumor treatment or cancer, then it can be reasonable to think about brain tumors when headaches recur. Otherwise, brain tumors are so rare, it would not be rational to think a person's headache is a brain tumor (unless there are other symptoms). People generally die of other things, not brain tumors.