I had a lot of stomach issues last summer after eating certain types of food. I noticed that sometimes after eating ice cream I had diarrhea after 1 or 2 hours. Last Wednesday, I ate at a Mediterranean restaurant during lunch and I didn't feel any stomach problems until the night. During the night, I got a really bad headache and I keep feeling full like the food is stuck in my stomach. I am also burping a lot. It's been two days and I still feel the same symptoms. In the past, I had similar problems after eating a heavy dish such as salami or too much pepper but the headache this time is stronger. What kind of problem I may have?