Even parents are humans, and when the time comes, they have to leave because their time is up.
I think we just use to forget about this, we like to believe we have time, there's still time for us and even for our loved ones, but in reality it can be any moment for anyone.
I'm like the girl in that movie, when I lost someone I love, I get frozen, I don't know how to react or what next to do no matter how I tried.
And yeah, we never know when the camera will stop rolling, we can always do everything we can to make every moment count, enjoy every bit of it, as much as possible and spread love to those around us.
Sorry about your mom, my her soul continue to rest in peace.
RE: If I die today, what I will regret.