Constant Headache

I've a pretty complicated medical history, but here's the basics:
* I had a gran mal seziure at age 8 mos old, and was on anti-seizure medicine until age 2yrs
*  At age 4yrs old, I was hit in the head with a baseball bat, resulting in a knot on my LT temple. Several XRays/MRIs were taken of this at the time, but they all appeared normal. I still have this knot
* At 18yrs old I passed out (possibly hit head, do not know) and awoke with a slight, dull-throbbing headache, concentrated at the LT temple area.

I have had this headache ever since. I literally have had some degree of a headache every day of my  life since. I have been through about 30 medicines and 3 neurologists to date trying to find the source of the headache, or at least a pain reliever for it. Nothing has worked. All EEGs/MRIs/CTs done show that the area of my skull where the knot is has developed into a "subdural arachnoid hematoma" but does not have any irregularities beyond some bone thinning. Scans have been basically normal other than that.

I've been to the ER over the pain on a few ocassions, but have basically learned to live with it. My headache pain sometimes will move to the base of my skull or to the top of my head, but always seems to start at the left temple, and always is a throbbing (pulsating) pain.

Last year, I spent 3 weeks in an ICU after having 3 gran mal seizures. I experienced rhabdomyolysis after being hospitalized, which resulted in acute renal failure, pulmonary effusions, and respiratory failure. I had to undergo several rounds of dialysis and thoracentesis before being released. No one has been able to figure out a cause of these seizures, or more importantly, if it might happen again. The EEGs taken immediately upon this hospitalization show "bilateral temporal sharp waves" as well as a "lot of Beta activity".

I have been under the treatment of a new neurologist since that hospitlization,and have remained stable on a 2000mg daily dose of Keppra since, but I continue to have these headaches. They vary widely in pain and are sometimes unbearable. The only consistent trigger I can seem to pinpoint (after keeping a 'headache journal' for 9mos) is a phonophobia. I have a pain pill the doctor gave me as a "911" but I generally do not take anything; the only thing that seems to help alleviate the pain is sleep.

Sorry if I sound like I'm rambling, but this is the short-short version of my medical history.  I'd appreciate any input/suggestions anyone could give me.
Thanks!