Hi my headache is not going away even after i have taken pain killer? Its a dull ache all over, but I have sharp pains in both temples. I have had it for 5 days and its just not going away. I have health anxiety and I'm really scared its a brain tumour because i have other neurological symptoms such as lightheadedness, flashes of light out the corner of my eyes and fatigue. Do you think its a brain tumour?