question: As soon as she sneezed she felt a sharp pain in her head. Front and back so bad to the point we took her to the er. After waiting and sitting for a while she felt better but still had a headache. They had her take a CAT scan and everything came back fine. Low to normal blood pressure, she's a smoker,  no diabetes,  everything else is fine according to the doctor she went to see. He also gave her celebrate to relieve any inflammation and to help with her headache but she says there is still something there.  What could be causing this?