Recurrent Stomach Infection, Burning Sensation. Foul Smelling Flatus. Taken Norflox. Vomiting, Weakness, Fever

hi i am 35 year old female, have recurrent stomach infections, endoscopy does not reveal any thing significant all tests are normal. Feel burning sensation sometimes only, but have a lot of gas frequently with foul smelling flatus. Three days ago i had discomfort in stomach with two bowel movements with stomach pain and then felt fine, next morning had fever and body ache which lasted for three days without any significant pain or other symptoms except lack of hunger and nausea, vomited once at night, took norflox 40 and ornof and third day fever went away, weakness persists. Please tell me what to do to keep my stomach healthy.