Tell me about the difference between a digestive infection and a digestive disorder. Thank you doctor!

Gastroenteritis is an infection of the digestive tract that causes diarrhea and other symptoms such as abdominal pain or nausea.

After eating lunch, I had a stomach ache around the navel that was very painful and vomited. I went for a CT scan of my abdomen and an ultrasound of my abdomen was normal. I took a blood test and the white blood cells were high, the pain lasted about 1 hour, then it got better and went away. History 10 years ago I had abdominal pain 1 time due to stomach. So the doctor told me the cause of the abdominal pain around the navel with vomiting?