Prescribed Pantaloc For Stomach Issues. On Anti Inflammatories. Suffer From Burning Sensation In Stomach, Bloating And Gas. Help?

Question: Hello, I have been prescribed pantaloc 40mg twice daily for stomach issues while on anti inflammatories for a hurt back, I fell and there seems to be a pinched nerve. I began two days ago, first day no side effects, second day began to get burning stomach, terrible gas and bloating. I have been eating basically dry toast and rice and water to alleviate the distress. I took my morning dose this a m and the pain was very bad, took Zantac and gas x , calmed it down but it still feels irritated. I did not take a pain killer today,and only one yesterday. I took naproxen 500 yesterday, could this be the cause of the flare up. I usually take Advil. I also have IBS which is in a flare due to the anti inflammatory meds. Normally my stomach tends towards gassy and acid but nothing as painful as this. Could this be the pantaloc, my doc is away on holidays so would appreciate a bit of guidance here.

So I was afraid that the pantaloc is causing the gas and pain. Could this be possible? Can I not just continue to take Zantac? What is the therapeutic dose of Zantac? Also, what will get rid of the gas? I've tried gas x works for a while then I'm bloated again with gas. Is there something better than gas x that would not interfere with other meds? Thank you kindly.