Hi I am a 17 year old male and the past 5 or so days i have experienced a pain at the back of the left side of my head and a pain behind my eye. The pain is not crippling and doesn't stop me doing day to day activities. I am really worried it's a brain tumour as everytime i tilt my neck to loom downwards it hurts in that area. I have suffered with cluster headaches for as long as I can remember however the slight pain and the back left of my head is one i've never felt. Should I be worried?