The term Karma or Karm in Sanskrit means actions words or deeds. It is also used to denote the spiritual principle of cause and effect. Your actions and intentions (the cause) influence the future of the person (effect). Some may argue that the effect is not limited to you alone but can also extend to your family members. Your son may pay the price for your actions so to speak.
Believers of karma transcend lives. They believe in something called Universal Karma where the actions and intentions of a person can transcend this being, and the effects may even be felt or experienced in another life. Your actions are being recorded in some cosmic balance sheet to be set off in the future. One life is not sufficient to normalize the multitude of actions and thoughts. To the believer, life will eventually catch up, and you will pay for what you thought or said or did. Perhaps!
There is something more simple that also happens. Call this emotional karma or psychological karma. This kind of karma is the impact that your actions and deeds have on your mind and emotional state. Regardless of your moral compass, your actions and deeds will leave an imprint on your mind. An intelligent mind will easily rationalize all actions. Say a person is the cause of some misfortune to someone else. The person may through artistic mental gymnastics even blame the trouble on karma. It is not his actions but your karma causing the terrible outcomes.
It would still leave niggling doubts, nay a sense of unease within. You may force the niggle into the shadows of your mind. You may dismiss or discard the emotion but it never really goes away. Repeat your actions over and over, and soon you are on a treadmill trying to escape no one but yourself. There may not be empirical evidence of Universal Karma but there sure as hell is evidence of emotional karma. All you need to do is look within.