Unfortunately, that sounds familiar. I too have been tested for many things and come back as a completely healthy person with unbearable pain.
I too am sensitive to my blood sugar dropping and avoid skipping meals. You mentioned hot dogs, nitrites and artificially smoked food triggered your migraines. I find that any preservatives (chemicals) trigger my migraines. This includes sulphites, msg, yeast extract, etc. There is a book that contains the "migraine diet" and it is also listed at this web page: http://www.kirchnerheadacheclinic.com/diet.asp. I use this as a reference guide and it really helps minimize my headaches.
I have heard of others who suffer the other symptoms of a migraine but not as much pain. That would be a nice change as the pain is the debilitating part for me. I find that my stomach gets upset, I get nauseous and have to go bed when my migraines are really bad. I hadn't ever thought of comparing it to the flu, but I guess the symptoms are similar.
Have you tried or discussed with your doctor a triptan medication? such as zomig, imitrex, axert? These might help abate the symptoms that are not pain related with minimal side effects.
That's very interesting that you feel well the night before you get a migraine. i have never heard of that before, but I'm not a medical expert. I just have my experience to go on and what I have learned by talking to others.