Severance offer, what should I ask for?

I was offered 12 weeks of severance after 12 years as a dental hygienist, and I have a few days to sign. This is my first time dealing with any of this. I do not want to leave money on the table.

I asked for two more weeks and a neutral reference. They agreed to the reference and added a week.

Read the release carefully. Mine included things I did not expect, like a non-compete.