Do I have a ulcer or hernia?

I'm four years out of gastric byp surgery. I have crazy heartburn which I take meds for but sometimes still feel the symptoms. I have pain right below my sternum and spontaneous gagging that has happened three rimes in the past year and has always occurred by waking me up from sleep. It's pretty much just me stopping myself from puking. These symptoms seem to be getting worse. I will be going to a doctor shortly but just wanted some ideas. Thank you!