Let us all know how the scopes go, I myself had one yesterday due to not being able to eat anything, they bounced between the idea of cystitis/gallstones/stomach ulcers and a couple other things but found no answers so they discharged me and sent me home with no answers and more pills. I know im not going through as bad as what you are on the food side of things, but know I can sympathise with you to an extent.
Are they giving you a general anesthetic for both procedures or just a local and sedation? I highly, highly recommend a general if you get the option, after the ordeal I went through yesterday I really can not recommend it enough, though apparently I am harder to sedate than most, so my experience was not typical and I had crappy doctors, so I'll bet your experience won't be as bad as I had.
R.I.P ~ Bubbles - 25yo tb mare - 13.04.2011 ~ 8:30am ~ passed away naturally and peacefully in my arms