Working a day job & 3rd shift job

I picked up a 3rd shift job at Pick 'n Save, 11pm to 7am. I thought it'd be an interesting experience as well as a way to make and save more money. The closest I've ever gotten to a 3rd shifter is when I bartended from 9pm to 4am. I finished my first three shifts and so far I actually really enjoy it! Its completely mindless work which is what I need for such late hours. I get to listen to my own music and take breaks as I please. The only bummer is that I also work a day job which can be either 1st or 2nd shift hours. So, if I work 3rd shift the same day, I end up working 16 hour days with only about four hours of sleep. I thought I was going to die, but I've actually been able to handle it fairly well! I'm hoping to work both jobs together for a month. We'll see how long that lasts.