The only thing that we suffer from at any moment is what we have yet to understand about ourselves. We suffer the way we presently do because we live in a small world, and our actions and decisions are based solely on the context of the information available in that world. We think we are always right because we act according to the limited thoughts and feelings that are given to us in this small world, and we think that these thoughts and feelings tell us the whole story, which they do not.
There is a world outside of, and higher than, this small world. All worlds exist in you--every force, light and dark--every possibility--all at once. Real life is a continual genesis of relationship, where every action you take affects the whole of life. If you want to help the entire world, then there's no better place to start than by doing your own inner-work. You can actually help another person by not hurting yourself!
Haven't we all made mistakes in the past? Yes, we all have. But why do past mistakes cause us pain in the present? Is it because the past has some power over us in which we have no choice but to suffer over what we have done. No, the real reason that past regrets and blunders cause us pain is that "we" resurrect and relive them.
We would never deliberately, consciously resurrect a painful past, but something within us does just that, and it creates the very karma--that circumstance or that event--that we claim is being forced upon us. The only authority that any painful thought-form has over us is our resistance to it. A painful past, which is not something that is outside of you, does not exist apart from your resistance to it!