I am glad to hear that someone is trying to actually help you. Usually a small bowel study is not as conclusive as an EGD (esophagogastroduodenoscopy - longest word in the world, which essentially means that they are looking at your esophagus, stomach, and first part of the small intestine). That is pretty much the "opposite" of a colonoscopy.
If your colonoscopy was good to go, this might very well be a "functional" disorder that is not able to be imaged or biopsied...i.e., we don't know what exactly it is. That is the case for most of the people that post on this site, so you shouldn't feel alone!
All that means is that medical science has not yet elucidated the source of your pain. That doesn't mean it's not real pain that you are experiencing. So they are not believing that you are "imagining" this pain.
I am sorry for the loss of your uncle. Is your consultant a primary care physician? Let us know how it goes.