Is Persistent Headache, A Sign Of Brain Tumour?

I keep having headaches, i went to the doctors today and he showed me that this has been recorded for well over a year. Im scared i have a brain tumour but then keep trying to reasure myself i dont. When i stand up in the morning i feel faint and i see flashing lights but this only last a few seconds. The headaches usally come on in the morning and sometimes ease in the day but paracetomal or nurofen doesnt calm it. Please help.