yeah, that is going to be a problem. the leaving out the candi sugar, that is. forgetting the og reading is no big deal, usually. the candi sugar would have raised your alcohol level, and affected the flavor of the beer. seeing as how that was the only sugar they sent you, I can see how you got confused though. the good part is, it will still make beer.
I've never seen a shop repackage a brew kit, but I would be pretty mad if they left that much stuff out.