Hi I can understand your concern... Noted you have diarrhea first then after constipation ... Are you taking stress ???? Here it seems to be functional bowel disease.... The possibility of chronic gastritis also present.... Here are few advise.... 1.Drink more water. 2.non veg , fatty food and fried plus spicy food kept limited in your diet.... 3.green leafy salad taken more 4.For constipation fiber supplement can taken... 5.oat contain fiber, zinc , vitamin E etc... So good for soothing.... 6.kiwi , avocado like fruits taken more 7.avoid stress and smoking... 8.Take oflox plus ornidazole combination drug... 9.avoid gas forming food like cabbage If still no resolution colonoscopy might needed. Take care...