Everyone has a picture of their life as they see it. Certain parts of your life are a bigger part of the picture. For me, the biggest parts were my roles as wife, mother, and teacher. I have a definite "before" and "after" in my life.
It's true that unexpected death messes with your world in a way few things can. Adding to this list, or creating a whole new one of your own, might give you just the tiniest roadmap inside a wholly disorienting time.
The stages of grief were not meant to tell you what you feel, what you should feel, and when exactly you should feel it. They were not meant to dictate whether you are doing your grief "correctly" or not. They were meant to normalize a deeply not-normal time.
Companion yourself. Care for yourself. Listen. Reach out where it feels good to reach, curl in when that is what you need. Make this season as much of a comfort to you as you can. And when it is not a comfort, know we're here. All these other grieving introverts: We get you. We understand.