If you are able to have Compassion and Lovingkindness for yourself simply by understanding your current challenges of being a human being, then you may not have to go more deeply into it. Especially if we have resolved some of our past Dukkha, it may not be something that's influencing our present actions as much as it used to do, and if we have a thought or remembrance of these things, it doesn't have an emotional impact in the mind.
But sometimes, if we haven't resolved some of our past Dukkha, a remembrance of this Dukkha will have an emotional impact in the mind. Then a thought is not just a thought that arises and passes, just a remembrance, because we still have emotional involvement with it. In these instances, we may have to do more work in the Compassionate/Lovingkindness or Forgiveness meditations to be able to let go of this strong emotional involvement we have with these memories of who we used to be.
If we are able to bring up and reflect on our current Dukkha, and if our past memories don't seem to have an emotional impact, then it's okay, we don't have to delve into the past. We can leave the past in the past. It's when these issues and the memories of them continue to impact us in the present that you may have to work harder in the Compassionate/Lovingkindness, to bring Compassionate/Lovingkindness for who you used to be and to see that the person who you used to be is different to the person you are now. Often it's difficult to resolve these things unless we see the change.