God is not this monstrous and vengeful God that some make Him/Her out to be. Sure He/She could be and I would not like to piss Him/Her off; however, He/She is first and foremost merciful and empathetic. All of us have sinned and fall short of the Grace that is freely given to us by God. You may yourself worry about things that you have done. God is not so interested in the things that we have done. God has forgiven us for them, though there are some conditions. Have we confessed what we have done wrong, at the minimum direct to God? Have we developed enough regret to ensure that we will not repeat the behaviour? Have we forgiven ourselves?
Once we have done this, then the issue that we need to focus on, is not what we have done in the past, but what we are doing today – in the present moment. How much are you striving today? Are you doing all that you can to be a positive contributor to society? Are you using the gifts that God gave you to assist others? Are you focussing on what is positive in your life?
Or do you take life for granted, complain, and focus on what you haven't got, what is wrong in your life? God wants you to be a person of action, someone who will get things done. The word Karma means action or deed; therefore, leave any wrongdoings in the past and be a person who strives for all that you can be today!