Should I negotiate my severance? after 6 years as an IT help-desk technician

I was offered 6 weeks of severance after 6 years as an IT help-desk technician, and I have a few days to sign. It has been weighing on me all week. There is a non-disparagement clause.

Thanks for writing this out. I went through something close to it 7 months ago, and it settled down once I kept a simple log of every call and form.