Hello~I hope that by now you are feeling better.
You could very well have caused a small hernia, especially if your diaphragmic wall is thin, so many folks that have anxiety have these Hiatal hernias. The fact that your acid reflux is no better tells me this could be the case. The only way it would show up is if the doctor did an upper GI, otherwise, they don't show up.
You mentioned that you were on antibiotics, these can cause some acid reflux issues as well. They take out the "friendly bacteria" If this is the case, then taking a good, high-p0tency probiotic would benefit you.
On a closing note, I would also see a chiropractor, mine pulls mine down. Also, some areas in your mid back could be impinging some nerves causing this issues.