besides looking at all the other factors, I am going to tell you to analyze the ingredients in your food.
I am willing to bet you eat a lot of processed foods. ( boxed foods)
What you describe is also a side effect of msg. Msg is prominent in majority of common boxed foods and the side effects are -
Quote:Side Effects
While food additives aren't unusual (for instance, salt is an additive), it is rare to include a food additive that can actually cause severe health problems. Some of the side effects of consuming MSG include:
burning sensations in the back, neck,
chest; paralysis; numbness in the same areas; tingling or warmth in the face, arms or back; nausea; facial tightness;
rapid heartbeat; chest pains, asthma attacks; drowsiness or cravings for other foods.
Reactions to MSG may happen at any time, from right after MSG is consumed to up to two days later.
Read more: Side Effects of Monosodium Glutamate | eHow.com
http://www.ehow.com/about_5066340_side-effects-monosodium-glutamate.html#ixzz1TmXUQga6
I know ehow is not a medical site, but it is a common news site so I picked that to quote.
But really, take a look at WHAT you are eating. If your reaction is that immediate, it IS coming from the source of your food. Eliminating problem foods will go a long way to getting rid of that horrible feeling.
but do not just assume that is 100% the issue. It is only a piece of the pie, possibly a very large one at that. Stay with your doctors too.