People always say that they want one last chance. One more try to do things. Regret is one of the stronger feelings that a pony can suffer. It is a reminder of something that they could have or should have done. Something that chases after them throughout their lives.
Sometimes it is worse. Sometimes, things change suddenly, and leave no time for anypony to do what they want to do. Things happen so fast that actions are left in stone, and nothing can ever change it.
There is no such thing as a second chance. There is only ever the mending, and that is a blessing for the healing it offers. When it is missing, nothing heals. When something is bad enough, some might contemplate simply lying down and never waking again.
Twilight wakes, and something is wrong. What could it be? She can find out.
But will she want to?