Prolonged-release of an orally drug taken in pill form is a "special feature", it's the difference between regular Adderall and Adderall XR.
There are patented techniques involved to make it work like that, generica manufacturers probably don't have access to those/leave it out to save manufacturing costs.
You can try taking the generica in smaller dosages, to compensate for their lack of prolonged-release, as the symptoms you describe sound like you are overdosing by taking too much in too short of a time.
Concerta doesn't need such manual dosage management, as it also has prolonged-release just like Adderall XR.