I Am Very Concerned As This Has Been Going On

I am very concerned as this has been going on for over two weeks. ever time I eat I get horrible stomach pain with nausea and diarrhea. I have also had a dull headache that is not responsive to excedrine or tylenol. I feel very weak, am shaky and tired, My doctor has prescribed zantac ans prilosec as I have GERD and IBS. I am also taking Zophran for the nausea. Nothing is working. I see my MD tomorrow. Any ideas that may help me today. Every food I eat is causing pain.