Our family home remedy is 1/4 teas baking soda in a cup of water, but not for those with hypertension. The body actually makes a nearly identical substance.
I have had many GI problems. If I become even slightly constipated I have those symptoms. I also have to see my GI doc every couple of years to have my esophagus stretched and esophageal spasms and belching a lot are symptoms that I need it done.
My nephew's mom had this, went to mayo clinic and found out her stomach was twisted.
If laxatives don't work maybe a GI work up is needed. Good luck.