A Diary That Takes Me Back and Forth Through Time and Space

I have a diary that I started keeping in 1995. I record major events in my life every few years, such as entering high school, entering university, getting married and having children, and immigrating. By chance, I discovered that this diary can take me between the current era and the parallel universe space of 25 years ago, allowing me to live in two different time and space at the same time, especially the time and space of 25 years ago. I can use my existing memories to change some life trajectories that have happened. After locking the small lock of the diary, I woke up 25 years ago. When I opened the small lock, I returned to the current time and space. If I slowly change who I was 25 years ago, will the current me in time and space disappear or will it change?