It's good that you're concerned for your daughter, but unless you get a difinitive diagnosis, you really can't say. You're right in your assumption that a Crohn's diagnosis is unlikely.
It could be anything from Gastritis, appendicitis to a food allergy, or even Celiac. One tell tale sign, for the most common type of Crohn's is a mass, lump like feeling on the lower right side.
They will likely do an ultrasoud, then if they suspect anything after that, will refer you to a Pediatric Gastroenterologist.
Good luck, hopefully nothing to worry about.