Depends what's going on. Its very different if I'm in the design phase of a project or assembly and testing.
I really enjoy CADing and designing in general. And I'm fine writing documentation, procedures, assembly instructions. Pretty smooth for me.
Once production starts and things go wrong, we need to investigate, fix the issues, and sometimes we're chasings ghotsts. This is the stressful part. I'm currently in it, and I'm pretty stressed these days.
Good thing I like a lot of people, got to police my thoughts all the time for everyone