What Causes Severe Pain In Epigastrium, Nausea, Vomiting And Dry Heaves?

Have been taking generic Zantac 2 times a day since finding out that I have a hiatal hernia. However, sometimes the severe pain in my epigastrium feels like chest pain....sometimes not relieved with additional Zantac. I have taken baby aspirin on occasion with the pain and it will help. Now I am having the pain more often and with it I have nausea and vomiting (dry heaving, because of Rou-enx-Y gastric bypass 15 years ago). Does this sound like something more?