Hi, 
Noted the history and understood the concerns. 
Combination of GERD and intestinal symptoms like bloating, gases, burping can be troublesome.
Surely, these symptoms are related to IBS and GED can be secondary to the gases, burping causing the GERD and thus pain in the throat, back and so on as you have mentioned. 
I would advise you the following:
Continue 
Pantoprazole.
Take 
Domperidone for motility regulation to avoid reflux.
As for the 
flatulence and other symptoms get stool tests of three consecutive days. 
Tests of blood for CBC, thyroid and liver functions.
Upper GI Endoscopy and 
colonoscopy.
CT scan of abdomen.These along with an opinion of a Gastroenterologist will give you the proper diagnosis and a plan for further medical management.
Control of stress and anxiety is the mainstay in cases of IBS and GERD.
Avoid the foods and beverages that cause the problems.
If there is an intestinal infection you need the medications like antibiotic, 
metronidazole to control infection.
Add on probiotics and activated charcoal.
Symptomatic treatment for the abdominal cramps and diarrhea helps further.
Hope I have answered your query. Let me know if I can assist you further. 
Regards, 
Dr. T Chandrakant, 
General Surgeon