(Concern) Tooth re-alignment

It has been about six months since I finished my orthodontic treatment. I had non-extraction orthodontics, but I didn't remove the interdental spaces, so there is a slight protrusion. However, the midline is subtly off.

It doesn't fit well ㅜㅜ Others say they don't notice or care, but I am very self-conscious when I look in the mirror. If I use the retention device properly, will it stop shifting? I'm worried it might shift even more. Also, I'm curious if it can be corrected again through re-orthodontic treatment.