Why do I feel sick after eating certain foods?

Why do I experience night sweats, anxiety, depression and lethargy, gas and stomach problems after eating any salty, fatty, or acidic foods? I get sick within an hour of eating, especially if I eat too much. It feels like a wave of exhaustion comes over me and I feel out of it and dreamlike. If I eat these foods at night, I get nightmares and wake up covered in sweat, feeling out of it, anxious, tired and depressed. I also get stomach ulcer pain if I eat acidic foods and also get these symptoms with it.