Laid off this week, where do I start? after 15 years as an accountant

They called a meeting on Wednesday and 15 of us were let go. I had been there 15 years. I would rather hear the honest version than the polite one. I have a box of my things and a short letter about benefits. Which steps were urgent?

Ask for your final pay, unused leave and any documents in writing before you leave, if you still can.