Layoff happened 15 days ago, feeling lost - any advice?

I was let go as an operations analyst this week and I am still in shock. This is my first time dealing with any of this. I have a box of my things and a short letter about benefits. What did you do in the first week?

Thanks for writing this out. I went through something close to it 12 months ago, and it settled down once I kept a simple log of every call and form.