Oh, Frogga! That sounds terrible! The only time I ever had that happen to me had nothing to do with RSD. I had an ulcerated esophagus, which my Dr. claimed was brought on by stress (????) and it was YEARS ago, so I don't really remember too much about it except I was miserable and off work for what seemed like forever.
Please, get it checked out, and do come check back in with us. Let us know how you're doing. And do this straight away! Don't keep us worrying!