UPDATE: GI Dr. Visit today!

Gawz, the small bowel series is icky, but shouldn't take too long (although it really depends on how fast your system is).  You'll drink 2-3 cups of chalky-tasting barium.  They'll start taking x-rays about 15-30 minutes after you drink it, and every 15-30 minutes after that until the barium reaches your colon.  For me, it only took the barium about 30 minutes to get into my colon, but that's almost crazy fast.  For others it can take up to four hours!  So bring a book to pass the time!

After the procedure, you will be crapping "ghost poo" for a few days afterwards.  It's white.  Creepy-looking.  Drink plenty of water and eat lots of high-fiber foods to get that stuff out.  Yuck!

As far as the breath test goes, I've never had one of those.  From what I've heard, it's a simple test and quick to boot.  Good luck with both tests!

Gawz, the consistency of the ghost poo will depend on what kind of day you're having.  I found the barium to have a sort of constipating effect, which is a relief for me, since I have the big D between 5-10 times every day.  I had formed ghost poos for about two days; for some people, it will take longer for the barium to come out.  Drink and drink and drink as much as you can.  You won't feel any discomfort after the procedure; I went straight back to work when I was finished.  It's very easy. 

The SBFT can illuminate abnormalities such as bowel wall thickening, strictures (narrowing), and other signs of inflammation.  If it's negative, that's a good indication it's not inflammatory bowel disease.  Unfortunately, there can be some false positive results.  For instance, the radiologist who read mine said that I had thickened duodenal folds.  Some GIs say that can be a presentation of Crohn's disease or other inflammatory process, while my GI up here told me that it was a non-specific finding that probably meant nothing.  A little confusing.  What other tests have you had?