I guess if this is more applicable to me after I change "super rough day at work" to "normal, soul draining day at work", I should probably also change "quitting my job" to "career change".
Your not alone, remember it's just one day. It can always get better! But if you've been unhappy for awhile explore your options. There is no harm in exploration.
Don't really like it though as it is a bs expression used by employers to discredit workers that do exactly what they were employed for and don't gift the employer their free time. You know, just like most employers don't do anything but to pay you the bare minimum that they can get away with all while expecting you to hand out gifts to them.