I believe that the human brain has evolved to store complex memories as emotion. It is easier to feel a certain way towards something than it is to remember the series of facts you have to consider before making a decision. For example; it is easier remembering the combinations of taste, texture, experience and what have you that made you like the dish.
Sometimes it might not be even that good but the experience could help you relieve a period in your life. Like you would evoke emotions whilst looking at a picture. The content if the picture might groom anger say if it reminded you of ugly a situation. Same way a simplistic scratch that you made in a pavement might just remind you of how far you have come.
Emotions then are purely for efficiency. You come to a decision much faster if you emote to it. The illusion might be that we live a life of reason. Yet if we traced our decisions with a sober mind might be shocked to discover that we have been mostly been creatures of emotion.
You are an engineer because you loved making stuff but not because your pastoral community needs engines. Reality is; you would have been of bigger help were you a veterinarian. It might even come out as unusual that you choose the path. However I believe that all stories indeed have causalities.
Unusual decisions are mostly out of pain. Of course judgment of usual or otherwise lies with the observer. Every observer carries around frames of reference based of individual experiences. Even a theater watching a movie eventually fights over interpretations. However most unusual decisions are meant to simply avoid a past experience which wasn’t up to your liking.
Should pain be revisited? Absolutely! If and only if it is for learning experiences. You might have missed some detail crucial to the overall interpretation. Revisited pain fades over time if you have grown to understand it; why it happened. It might even disappear if you misread a situation or understood why events took their form.
Pain like any other emotion is to be held in equal regard; appreciated. It serves for an efficient future where like situations are not met with random kicks but coordinated kicks and pulls which steadily enable you to swim across or out it.