^ are you disappointed in yourself? if you are then get started on fixing it so you don't have to regret it, if you're not then don't sweat it, parents wanting their children to live up to their expectations is selfish, understandable but selfish, maybe explain to her that her disappointment hurts you and that at the end of the day it's your life, if she expresses disappointment knowing it hurts you then that's just fucked up.
as to the OP i'd have to say nothing, I've made many mistakes but I wouldn't change them