My Grandson Is Autistic And Is On Concerta. He Got

My grandson is autistic and is on concerta. He got on it over the summer. For the last few months and especially lately, he has gotten to where he gets mad easily. He is almost 15. Had a fight at school before Christmas. He was hit first, so he hit back. Friday, he hit the same kid first. He has never acted like that. He is always a sweet kid. He played basketball tonight. Was very angry after because he said he played bad. He has played worse and never cared. Does this sound like it could be the meds? He is taking no other meds.