I recently started having the tingling/pain in my left arm, joints and upper back. It wasn't until I found this sight that I realized these symptoms are related to GERD. Also have an off balance feeling.
Hi and welcome to the GERD forum.
Since you have ruled out a heart issue with the testing you have had, I would suggest you see a GI Dr for more testing....
There are diet and lifestyle modifications you should consider to help with the symptoms you have......you obviously have a feeling it may be reflux since you posted in this forum.