Quitting an understaffed job?

I recently posted about how work has been extremely stressful and overworking me lately. I realized no job is worth sacrificing my mental and physical health for so I decided to quit. I have an interview for another job lined up Monday and I was gonna wait until then to give a two weeks notice, but I dont think I can take another day of working 12 hours. Im on the verge of a breakdown. I just sat in my room crying for the past hour, stressed about the fact i have to work again tomorrow. I feel like shit because we are understaffed, but I feel even more like shit because of how the stress is affecting me. If I could have quit today and never gone back, I gladly would have.
Quitting an understaffed job?
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