Hi,
I don't have severe Gerd, but I do have a small hiatus hernia and minor acid reflux - I also have chostochondritis and have had all the heart tests, which were fine.
My chostocondritis is solved by ibuleve (anti inflammatory cream) My hernia produces a lot of burping so you may want to get that checked out - but it is now all under control with 1 omeprazole and 3 domperidone (stomach motility drug) and I have had no chest pain since.
Hope that this helps.