What could this be?
This forum is for questions and support regarding neurology issues such as:
Alzheimer's Disease,
ALS,
Autism, Brain Cancer,
Cerebral Palsy, Chronic Pain,
Epilepsy,
Fibromyalgia, Headaches, MS, Neuralgia, Neuropathy, Parkinson's Disease, RSD, Sleep Disorders,
Stroke, Traumatic Brain Injury

You can see a comprehensive list of symptoms in peer-reviewed journal articles under "Symptoms and Characteristics (peer-reviewed literature)" on my website:
http://www.openeyepictures.com/underourskin/uos_resources.html
Fewer than half the people with Lyme ever see a tick bite or a rash. The longer you have Lyme, the harder it is to get rid of.
I would strongly urge you to run to a Lyme-experienced physician, which you can find by typing in your location to "Flash Discussions", then "Find a Physician" here:
http://www.lymenet.org/
And you can also enter your symptoms under the "Medical Questions" section, and you can see what other people with similar symptoms think.
KrisKraft
http://www.lymediseasefilm.com/
I also doubt that migraines or migraine variants are your problem. This is a common misdiagnosis by doctors who are not headache specialists. Migraines are almost always characterized by pulsating pain in one region of the head. Your pain is not pulsating, but its "come and go" nature makes it 'paroxysmal' (in medical terms).
Sinusitis is also a common guess, but the specific locations and stabbing type of pain make me suspect some sort of cervicogenic (caused by something in the neck or cervical spine) headache, such as occipital neuralgia/neuritis. I think a trip to a neurologist is a good idea, though it may be better to see a pain clinic doctor first.
Good luck with your health, and please let us know what your doctors come up with.
JC: "Given that you've had headaches for a long time without other significant symptoms until now, I doubt that Lyme disease is your problem."
K: I just got back from a talk by a prominent Lyme clinician, who said that people can harbor asymptomatic Borellia for years, and it can flare when the person has a stressor, such as pregnancy, a car accident, a vaccine, a bad cold, etc. The latest thinking by researchers is that Borellia follows the Relapsing Fever and Syphilis model of infection, where the organism can essentially go dormant in a cyst form, embedded deep within tissues, then come out again when the conditions are right. (Read the Brorson's papers for more info.)
JC: "Lyme disease is a possibility, but it also happens to be one of the more common "guesses du jour."
K: I think Lyme needs to rise in the hierarchy of "educated guesses" when someone presents with multisystemic, wandering, unexplained neurologic symptoms. Unfortunately, the CDC is publicly downplaying the incidence of this disease. While their published surveillance criteria claims there were only about 20,000 cases last year, if you read the fine print in their 2004 MMWR report, they admit that these cases are underreported by "7 to 12 times." That means there were really about 200,000 cases in 2005, more than the reported US cases of AIDS and West Nile combined. I think for people who've been seeking answers for a long time, it's certainly worth spending a couple hundred bucks testing for it. Just make sure you order the ELISA AND the Western Blot IgG and IgM tests, because the ELISA is notoriously unsensitive, missing over half the positive cases.
I stress rational, since it is the doctors who need to go the extra mile when it comes to Lyme disease and other vector-born illnesses. The degree to which these illnesses go under-reported is matched by the hype of many well-meaning Lyme-awareness supporting zealots, with the true measure of the risk to public health probably in the middle of the two extremes.
I have no qualms over kriskrafts objections, as long as we use symptoms to separate the zebras from the horses (and vice versa).