I don't know how many images of lungs you've looked at, but have you ever noticed that our two lungs are not symmetrical? Check out this medically-accurate image that shows that the right lung has 3 lobes while the left one has 2, and the left one is also a bit smaller than the right to make room for the heart.
Even though we sometimes hold up balance and symmetry as an ideal that we should strive for in our bodies, as though being "imbalanced" is inherently problematic, the truth is that our bodies are not actually evenly-balanced left-to-right to begin with. We don't need to look or feel even on both sides of our body in order to be healthy, functional beings. Asymmetry is a natural part of who we are!