i have been having a severe headache for the past 5yrs

i have been having a severe headache for the past 5yrs now and the headache is not constant in one place, it almost every part of my head including my neck and i have been to the hospital several times without numbers but the doctors keep telling me that it is not possible i have brain defect and be talking to them as i am talking, i do not know what to do, and i have taken so many medications, but all is to no avail, but still i am still having the severe headache. please what should i do?