Hi Poppet,
I'm new here and not sure what's been posted before, but like you I struggle with a lot of food allergies/intolerances. My symptoms are different than yours (some not so severe), but I find I'm getting intolerant to more foods by the day.
By all means, see an allergist. However, some allergists will not consider you as having a "true" allergy if you do not exhibit traditional allergic reaction symptoms. In my case, my "allergies" are merely considered intolerances because I don't have typical allergic reactions.
I have been trying a few things to manage my food intolerances - including avoidance, but that doesn't necessarily seem to be doing the trick. I seem to be finding new intolerances every day.
I am currently trying NAET (or NAED) allergy treatments. They are performed by an acupuncturist. I have no idea if it works, but I'm willing to give it a try. I'm tired of not being able to eat anything.
I've also found a number of recipe books quite helpful. My favorite is The Allergy Self-Help Cookbook by Marjorie Hurt Jones R.N.
I also have the Freedom from allergy cookbook by Ron Greenberg (Paperback - April 1996). I don't really care for the recipes in this one as much, but it had a lot of great info in the introduction regarding nutritional requirements and food families (food rotation diet).
I am also trying colon hydro-therapy to rid some of the toxins from built up waste in my colon. I have a lot of other health problems and I figure it wouldn't hurt. I've really noticed an increase in energy and I have a little more color in my cheeks! I'm not doing this under medical supervision and I'm not sure how wise that is, but your health care provider might be able to support you if you ever feel like giving it a try. I got the idea from reading I Was Poisoned by My Body: The Odyssey of a Doctor Who Reversed Fibromyalgia, Leaky Gut Syndrome & Multiple Chemical Sensitivity, Naturally by Gloria, Ph.D. Gilbere (Paperback - Mar 2007).
I hope some of this is helpful. (I hope it's ok that I'm recommending specific books!
BTW, I'm "allergic" to corn, wheat, sugar-based foods, cilantro, bananas and other tropical fruits, soy, dairy, yeast (?), nuts...... I also have sensitivities to latex, chemical scents and colors, dust, grass, cats, dogs.....
I feel your pain!