We're not always happy with where we are in life. We see ourselves as failures if we haven't become what we'd hoped for. We fear others criticize us as harshly as we do.
But you aren't your shitty job. You aren't a part-time warehouse job, it's just what you're doing for now, as long as you keep trying to improve.
You aren't 'where you are', you're 'where you're going'.