Its difficult to say any one thing that will work for you. However I believe if you haven't already many of the cleanses suggested by Dr.Schulze can be of great benefit for people with chronic allergies, especially MCS. Check out the Natural Healing forum for more info on this.
Of course you'll find great info at The Truth in Medicine Forum regarding herbs to strengthen your adrenals, which although may not solve your allergies will greatly assist your body in dealing with the reactions you are having. I'm in a similar situation where certain chemicals or allergens in the air will set me off off into a breathless dizzying panic attack. Some herbs such as Astragalus & Amla have been of help.
I'm trying another homeopathic form of treatment that is specific to severe allergies. If I find some more relief I'll be sure to let you know.
In the meantime I personally wouldn't bother with the adrenal fatigue test. Too much money, can be a hassle and in the end doesn't necessarily tell you anything that can be of use. If you suffer from allergies your adrenals are going to be in a weakened state. However if you are looking for a test I'm just pulling up a link from another thread in the forums here http://www.canaryclub.org/diurnal-cortisol-4x-zrt.html
parasite tests are often in-effective in detecting anything of note, and you can get caught up in testing while the problem worsens or worse get back a clean sheet but in fact have a parasite issue going on.
In my opinion you're better off doing a thorough parasite cleanse and paying attention to your improvement. The same goes for Candida, better following the diet consistently, using some herbal anti-fungals. Sort of the mentality of shoot and ask questions later but often people just seem to run around in circles looking for answers when they just could have felt better sooner doing some cleanses. Just my opinion. Herbs can be found online in bulk powder form at places like rosemountainherbs so you can take effective doses of them.