What about a doctor.

Is a not hard acute form of gastritis thus remedies are not using, as on early stage is diet use on  2  days melting of, are tea with rusks, if strong hurt, thus use almagel or almagel a  within 2 months before meal, on acute a chronic and spasms are spasmolitics use of papaverini, reglan, nospanum.
On hard case when secretion is bad, a patient uses chloride oxygen acid and stomach juice remedies, and very often inflammation has of poisons is toxic gastritis, thus here is needing hospitalizing for cleaning of poisons,after getting analgetics,spasmolitics as baralgin with nospanum and dimedrolum, or on hard case with vomiting is aminazin or diprazin.
Symptoms of gastritis are same,like in gastrointestinal diseases other, as somethones belly aches meaning on infarcus myocarditis, thus gastroscopy is right diagnosis.