Your pain sounds like it could be IBS, however, it could still be a lot of things. What sort of tests has your doc sent you for to better conclude you have "nothing"?
NO, whatever you do don't follow that diet. Well at least don't follow the apple part. Apples are notorious for causing gas and bloating. Bananas are good to help hold your intestines - but be careful if you're prone to heartburn... Bananas are super acidic. Unless you have a sensitivity to gluten you should be fine with toast and rice.
Have you taken any OTC meds for the gas? Beano and Gas-X seem to work pretty well. For the pain (cramps) some of us use a heating pad. It seems to work pretty well too.
Good luck and I hope you keep posting.