Should I negotiate my severance? after 13 years as an administrative assistant

I was offered 13 weeks of severance after 13 years as an administrative assistant, and I have a few days to sign. I worked as an administrative assistant before this. I do not want to leave money on the table.

Keep everything in writing and save the confirmation numbers. It saved me later.

Ask for the offer in writing and do not sign on the spot. A day or two to think is normal.