Chest pressure is a very subjective term. I've had what might be considered "pressure" but I call it a "lump" feeling--ca.
Don't worry about
the PH monitor. It's more of a wire than a tube, and it's NOTHING after the manometry test. You shouldn't avoid it just because of your discomfort with previous tests. Once the place the wire, it's not bad at all. The most annoying part of the test is that you have to be off PPI's a week or two prior (You can take a Zantac type med until a few days), then just Maalox until the day of the test.
You'll be glad when it's removed, but it's more of an inconvenience and annoyance than anything else.
It will tell if your chest pressure sensation is caused by acid escaping into your esophagus, creating injury to the delicate tissue.
Good luck getting to the bottom of your problems. Try to be patient, and don't panic. You will find an answer. Unfortunately, the tissue that lines your esophagus is very delicate and takes a long time to heal, once it's inflamed.
We're all here for you! Hang in there.