The last few times that I ate salmon I had a very painful reaction. It feels as though something is pushing its way up my throat from my stomach. It happens about 5 minutes after I eat and feels like my chest is being pushed outward from the inside. Once it starts it goes off and on about every 45 seconds for 10-15 minutes, I'm not sure why this is happening because I have never had any type of reaction to salmon, or any other foods before. It also forces a lot of saliva up my throat so it pretty much drains out of my mouth. It has also happened a few other times, for example: when I ate a pollo asado burrito at El Pollo Loco I had a light reaction (wasn't as bad as with salmon though).

Any help as to what this might be would be appreciated.

Thanks,
Matthew