your tooth symptoms are familiar to me!
about 5 years ago i had a root canal that kept hurting. the endodontist insisted he had "gotten it all" but went back for a second look/try. he did an apicoectomy, and said he was "sure" he'd gotten it all now!
(that was 3 stitches and $1000 later)
months went by, then nearly a year, and i still had pain.
the guy refunded 75% of the money i paid and said i needed to see a specialist.
well...years later, and about 7 dentists later...i still do not have a crown on that tooth that was prepped for a crown way back then. luckily this still-painful tooth is toward the back....
fast forward to years later and strange nerve pain/problems apparently due to other surgeries for completely different things and i have been diagnosed with various things, but the intriguing one that explains it all is:
341.9 Demyelinating Disease of Uncertain Origin
which apparently just means your nerves are messed up (parts wearing away like a bad wheel bearing on a car!) and therefore painful and sensitive.
as for your facial pain--
i had a tonsillectomy in Feb 03 and had complained of new, strange pain almost exactly like what you describe. about 10 doctors later...including 3 otolaryngologists...i saw a neurologist who said, "glossopharyngeal neuralgia."
aha! that's it!
there are several nerves in the neck/head area and it seems that when they become troubled by surgery, swelling, infection, physical injury or surgery, they can act haywire. this sounds like what you have.
it has taken me 11 doctors to get where i am now...but i will say that if indeed your trouble is a nerve problem you'll note that it is normal to have MRIs that show nothing wrong, physical exams that show nothing wrong, blood tests that show nothing or are inconclusive, etc. the only way the docs can say "yes, it's a nerve thing" is after they dissect the annoying body parts.
what can you do? see a neurologist. read the Singapore Medical Journal which can be found online. read an anatomy book. look at the various nerves and trace them in the head/neck/face areas and map out your pain. then explain to your doc. most likely they can give you meds to help make the pain "go to sleep," as it were.
you may take neurontin, zanaflex, nortriptylene, etc. like many neuropathy patients. or you may be prescribed viscous lidocaine (which is my latest RX, tho i have not gotten it filled yet due to the holidays).
i am ready to try the lidocaine to put the nerves to sleep, at least for a while.
the pain for me starts in the a.m. with a feeling of a blade of grass in my throat, a sore, lumpy, non-obedient tongue that won't talk right, then pain radiating through my throat, right eye, right ear, up to the nose, etc. much like what you describe. most days i can look in the mirror and my right eye is swollen as well.
i've gotten all sorts of diagnoses (DX) from all sorts of docs--from a family practioner to dentists, ear/nose/throat docs, different neurologists, psychiatrists, etc. some said--depression--my imagination--slow healing--injury--complex regional pain syndrome (crps)--systemic nerve disorder of unknown origin/cause/cure--and so on.
sometimes you have to just try to treat the symptoms so that you can go on with your life. you probably have people that depend on you and you want to be there for them. well, keep searching. keep looking for answers. your life should be as pain-free as possible, not only for those who love you and depend on you, but for your own sweet soul as well.
as i said, it took me five bloody years of searching (and way too much money) before i found a pain management group at a local university that is going to use a team effort to treat this mess i'm in. i've also decided to donate my body to science--i hope they learn something from it!
good luck to you--and don't give up!