Why do I have chronic stomach pain and diarrhea even after treating for it?

Question

Hi doctor,

I have a couple of questions and hope you can answer them.

This summer, I had a gastroscopy due to pain in my stomach. I underwent a biopsy and was diagnosed with Helicobacter infection and chronic gastritis. I took three different antibiotics, a tablet of Nexium, and a probiotic for 14 days. It was a tough treatment with side effects (diarrhea). After the cure, I feel that I have become worse. I have reactions to certain foods and have diarrhea approximately once a week. I have lots of air in my stomach. I cut out coffee, milk, and sugar and take no medication. I have done lots of blood tests and stool tests. The test were negative for Helicobacter (feces test), calprotectin, bacteria, viruses, lactose, and celiac disease. The food panel was negative, and I have no food allergies.

What do you think? Should I take some probiotics?

Is it the intestinal flora that is destroyed?

Kindly help.