I have read your question,
Generally Irritable Bowel Syndrome
Shows Symptoms like Diarrhea but there is no vomiting symptoms , hence i think you dont have irritable bowel syndrome .
I think You have chronic Gastritis
, I recommend you to have soft diet
, avoid spicy foods, and stress, If the symptoms still persist, I suggest you to consult gastroenterologist
I wish you a good health,