i read your query,
there are lot of reason for head ache, without proper history,it is impossible to get into exact diagnosis
In recurrent unexplained chronic headaches
keeping a "headache diary" with entries on type of headache, associated symptoms, precipitating and aggravating factors may be helpful. This may reveal specific patterns, such as an association with medication, with certain foods.
you have to be precise in saying the nature of headache like throbbing ,pricking which helps in precise diagnosis.
do you had any head injury
before,it too a reason of chronic headaches .
if you are taking any medications consult an physician about your symptom with the prescribed medications.
get well soon,
regards g.surendiran general physician