I'm going to quit my job in the middle of a shift and not come in the next day
Why are you choosing to leave your job this way?
I just need a break. It's hard to explain.
If a job is making you this stressed then you shouldn't stay there. Jobs are not worth hurting your mental health.
Take this job and shove it.
If your job is making you unhappy, you should leave to protect your mental health. It's important to find a job that makes you happy. However, you should give a proper notice to your current employer so that you can use them as a reference in the future.