Thanks for writing to H.C.M. for your query
I have gone through your clinical history regarding severe stabing pain behind the left ear, it remains for a very short time usually it comes and goes in a same speed and happens several times in a day . This typical history itself says that it is either a nuralgic pain or a vascular ischemic pain.
As far as nural pain is consider it may be due to cervical spondylosis
of upper cervical vertebrae
as cutaneous supply of that particular area comes from c2 and c3 spinal nerves. Osteophyts may irritate the nerve root
to menifest this pain.
Blood supply is from posterior auricular branch of external carotid artery
of this branch may give rise to vascular pain due to ischemia.
of this arterial supply will also give such type of pain as occurs in MIGRAIN.
To confirm these possibilities these investigations are necessary-
(1) M.R.I. of cervical spine
(2) Doppler study of posterior auricular artery.
(3) Blood- CBC, Lipid profile
With the help of above investigations and good clinical examination one may reach to correct diagnosis which may be plan for treatment.