Severance agreement arrived, need a second opinion, sales associate here

I was offered 15 weeks of severance after 15 years as a sales associate, and I have a few days to sign. I would rather hear the honest version than the polite one. I do not want to leave money on the table. Should I see a lawyer?

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

An hour with an employment lawyer cost me a small fee and made me feel much safer about signing.