What Causes Severe Gastritis Along With Bloating Of Abdomen?

I have had bad episodes of major gas and bloating under my right breast I have had my gallbladder removed already . This pain starts out like a growling rolling burn then it starts to tighten up like a vise is squeezing my chest the pain eventually goes to under my shoulder blade. If I burp it feels a bit better the episode lasted 3 hours last night I couldn t really lay down for a while. I took my omeperozole and then later pepto. Help please!