Honestly, I think emergency/retirement funds can never be big enough. I would just keep tossing any extra money at it until the anxiety subsides.
I think the amount is different for everyone. For pessimistic people with anxiety (me!), getting rid of anxiety completely means “I can make it until I can collect CPP/I can live on CPP.” (Canada Pension Plan, our equivalent to social security). But it’s a scale… I feel less anxious the closer I get.