What Is The Best Medicine For Stomach Pain And Gastritis?

I have a gastro problem since I was a teenager. I am 37 yo now. One day a friend suggest me take dogmatil because doctor prescribed it to her aunt with the same symptom like me. I browsed the internet and find out that drug meant to be for a mental health problem patient. But I already used it several times everytime my stomachache relapse and it worked. Before taking dogmatil I also sometimes take omeprazole. Oh and by the way, I have ever go to the doctor once and he prescribed a drug (I forgot the name, it was syrup) and also vitazym. I used both of them everytime the aching relapse until the syrup run out. And I continue take vitazym along with either omeprazole or dogmatil. So, which drug actually suitable for me? I only suffer twice or trice stomachache this couple years, since I got new job. But before, from 2010-2013 I suffer a lot of times stomachache, every month -it relapse 4 times in a couple week on october 2013- and I was unemployment those years. Is it have anything to do with stress?