You could have had earlier symptoms when you were 7, but it is very rare to have Schizophrenia show up that early. For the most part, the symptoms do not show up until closer to late teens or early 20's. It usually has nothing to do with intelligence. Many people with a high IQ get Schizophrenia as well as those of average or lower intelligence. It is like saying only low income people get cancer. Anyone an get Schizophrenia. It just doesn't show up until later. Your issue may have been more about a possible learning disability rather than Schizophrenia. If you can get evaluated by an Educational Psychologist that would give you the answer you are looking for.
Ok, I'm going over to the new question to help you there!