Hi,
There are many types of headache and in the majority of cases the underlying cause is not serious. However, it is important to exclude any serious conditions. You do not mention any other symptoms other than pain and you do not mention whereabouts in your head you feel the pain, front or back of your head? Are you experiencing any visual disturbances such as flashing lights or tunnel vision? is the headache worse when standing or lying down? Do you feel nauseous with it?
Do any type of painkillers help?
There are other questions that would be relevant to ask and therefore, I would recommend that you visit a neurologist who specialises in headaches. There may be a place for a CT or MRI scan.

Hello,
Thanks for the inquiry,
You say that you have chronic headache for 20 years, recently it got worsened. You have not mentioned any associated symptoms like nausea and vomiting. The causes of headache may be in the cranium (Primary) or elsewhere (Secondary)
Few points regarding Headache: headache may be -
Primary: may arise any part of the cranium like ear, sinuses, throat, muscle, nerves and bones etc., And the tension linked migraine like pain (one side of head) or rare a condition called as trigeminal neuralgia.
Secondary: cause may be elsewhere like neck muscle and bone, excessive intake of painkillers.
Your headache is in severe form and needs prompt investigation and treatment Seems to be Primary and tension associated. If your headache is on one side only it may be Migraine.
My Advise: Start with CT brain – if there is no problem then as per Dr's clinical examination and advise
Wishing you quick relief from Headache
Best wishes for you