The best person to tell you more about your son is your son! Since he is very bright and your relationship with him is good, you start with two plus points. It seems to me that his time is full of activities. That is a long list for a 7 year old! Talk to him and explain that if he takes an interest in studies, he will come upon exciting scientific facts and stories of adventure and so on. There is an inherent temperament of a person. Perhaps, he tends to be impulsive, wishing to move on all the time. Let him learn one game or art, which requires patience and deliberation, maybe Chess.
Also make sure that he is not having Cola drinks or too much refined sugar in his diet. If possible, each of his parents should have a special time reserved for him.
Make some rules for him and be consistent in keeping them. Stop buying new toys for him till he gets a sense of responsibility. Being with an Ayah throughout the day may not necessarily be the best thing for him. She probably gives in to every demand and he gets a false sense of power over people. Let her continue, but see if your son can spend some more time with boys and girls of his own age.
If all these steps have no effect, try and see a Counsellor, not a doctor.