Mine goes to my arms, hips, legs, back,
in between shoulder blades, fleeting
pains in the
chest, sides, or even
in the feet.. Weird ! .. you would be able to tell by pressing on the area- and it will make you burp and afford pain relief, or by doing chopping - like massage to where the pain is with same result.. I think your guess is right. Its gas from acidity..
To address formation of gas, I take "anti gas enzymes" Beano did not help me, not antacids either..