Why past perfect

Dear teachers,
Please help explain why the past perfect is used here,not the present perfect:

" Although this story has a happy ending- at least for me- I had never been ( HERE I UNDERSTAND WHY )as scared as I was that in junior high school . It happened so many years ago that I hadn't thought ( HERE I DON'T UNDERSTAND WHY)about that terrible day in a very long time until today.

Thank you in advance