The other issue is that there is no cheap and easy cortisol test like there is for blood glucose. As far as I can tell it would be possible to develop such a test, but nobody has done it yet for a number of reasons (lack of demand, cost, FDA approval, etc).
If someone were to [1] figure out a definitive test for burnout/CFS and [2] develop/patent a home testing kit they would be very rich and help a lot of people into the bargain.
As for Teitelbaum: while he does have some useful stuff to say, he also peddles a lot of quackery.
http://www.ncbi.nlm.nih.gov/pubmed/10633533
The 24-hour saliva cortisol test costs about $100 and should tell you a lot:
http://labtestsonline.org/understanding/analytes/cortisol/ta...
There are definitive clinical (non-blood) tests for hypothyroid (I mentioned several of them), there are also ways to test for FM/CFS (muscle recovery among others). They just don't get used a lot.
As for quackery -- the only quackery I read in Teitelbaum's book was about the allergy treatment and it's not any more or less quacky than acupuncture (where the research was discredited) so I consider it harmless. Every "canonical" scientist has some kind of nutty side, from Isaac Newton on down the line. (Note: Not comparing Teitelbaum to Newton whatsoever. It's just an ideal, extreme, example.) Everything else in his book is supported with research citations. I've checked them, and others, because I followed his advice.
[1] http://jama.jamanetwork.com/article.aspx?articleid=400116
If your morning cortisol is above a certain level or below a certain level; if your morning, before-you-get-out-bed axillary body temperature is above or below a certain temperature (under 97.8 or above 98.6); if your blood pressure deviates by a certain amount over a 16-hour day; if your average temps deviate by more than 0.2 F from day to day; if you have post-exertional malaise… you have an HPA malfunction of one kind or another.
I'd say "you should also get your thyroid checked" but the blood tests for that are atrociously useless. Check the symptoms. Low body temp, especially in the morning before you get out of bed (mine ranges from 96.5-97.4), slow heart rate if you're not an athlete (mine is 50-60 bpm and I am NOT an athlete!), puffy face/eyes, myxedema (non pitting) swelling/thickened rubbery skin on your upper outer arm or shin, changed ankle-tap reflexes, very cold extremities, Raynaud's phenomenon, etc., those are the signs that are actually diagnostic of a thyroid insufficiency.
These are how doctors have diagnosed and treated low thyroid successfully for a hundred years. The blood tests are a new thing but they aren't very indicative of actual dysfunction (or function).
All of the above is like a lot like low blood pressure. Low blood pressure is only defined by numbers when it becomes dangerous to life. Otherwise, you're diagnosed with low blood pressure if your blood pressure is "normal" or below and you have symptoms. E.g. I have low blood pressure at 100-110/60-70 even though that's considered just fine, because I feel faint when I stand up and other symptoms.
Generally, the best resource I've found is _From Fatigued to Fantastic_. It helped me get much, much, better.