What is wrong with me?!???

Hello.  I originally asked this in the "Ask the Clinician" section, but that was before I knew there was a forum with memebers!  Even now, this post isn't where I thought it would be.  Oops.  My apologies to the experts for the duplicate.  Without knowing if my question will be answered or not - I thought I would take the chance and ask here.

I am writing this question out of complete frustration with my headaches and lack of care I have received from the medical community.  I have suffered with chronic daily headaches for the past eight years and have been to several doctors and been prescribed several (19!) different medications.  Some have taken the edge off the pain, but none have provided complete relief. 

I have seen two Neurologists who are "Headache Specialists".  However, both of them immediately prescribed medication and did not send me for any type of tests.  The most recent Neurologist says he "thinks my headaches are vascular" and the symptoms are somewhat related to migraines, but are "atypical".  

I am frustrated because no doctor has told me what is causing the constant daily pain and has not diagnosed me.  I have eliminated all known "triggers", including overuse of OTC medicines, but I still have a headache.  It is always on one side, behind my left eye and at the base of my skull.  It is a daily dull ache and when I have "episodes" several times a week, it literally feels like someone is sticking a knife or ice pick through my eye socket.  Sometimes I have nausea and light sensitivity, but not always. 

Also, my headaches disappeared COMPLETELY both times I was pregnant. I have been on birth conrol pills and had the Mirena IUD and the headaches did not change or get worse.  But, my headaches ARE worse the day before / of my period.  Go figure... 

I have an eye exam including dialation, been to an ENT, treated for sinus problems, had a CT scan of my sinuses and everything has been normal.  I have told every doctor that I had a head injury - I was hit in the eye (the one that hurts) with a softball and knocked out when I was 12.  None of them have thought that was important or noted it in my chart.  Could that be related?  Is this a "variation" of a migraine?  Could an MRI help? 

I feel so helpless and hopeless.  Everyone says "change doctors", but I have seen so many and I am tired of being the guinea pig for new drugs!  I am currently on Zanaflex and Depacote.

Please help, if you can.  I appreciate your time and attention.  Thank you.