Stuck in the past

Why is my mind always wandering to the past ? i constantly think about the past, every mistake, every traumatic event, it's been like this for years and only recently have i realized how fucking tiring and unusual it is. There's truly not a single moment where i'm not thinking of the past, i don't understand why ? it happens automatically, it's just where i'm always at mind wise.

is there a specific name for this ? or is this actually normal ?