Any punishment or reward in the Afterlife will come from yourself and will be proportionate to the level of the (mis)deeds and to your willingness to accept responsibility for them.

Just to concentrate on punishment...It can take a while to understand what you did wrong and there will much discussion and thought over every act against others until such time that you genuinely accept responsibility for such deeds and truly regret them (repent is a bit Biblical). This process can be quite painful and will be like going through your own private "Hell", which does not exist a a place but as your own feelings of guilt and regret for those bad deeds done against others.