Hello! I Had Upper Endoscopy Two Weeks Ago, It Didn't

Hello! I had upper endoscopy two weeks ago, it didn't help my swallowing, tomorrow I suppose to get a repeat, the problem I am having now is stomach pain ! It started last Wednesday! I been eating instant potatoes! That's what I been eating! I been taking prilosac OTC! It started as diarrhea, now the diarrhea stop, now continue stomach pain!