Quitting Less than 90 days???

I'm a Med-Surg RN with a 1:5 nurse to pt ratio working in a Level 1 Trauma hospital. I like that I'm never bored and I'm always learning something new.

However, almost everyday I get off shift, I feel like a failure. I'm also a single dad and before I started working, my soon to be ex worked days and it worked out for the both of us with our 3yr old son. I have no family here. I also feel like I'm sleeping my life away when I'm off because technically, I do work on my days off up to 7am so it feels like I have no days off. My unit has a dayshift position open, but at this point, I see Med-surg isn't for me. I've always preferred a day clinic setting and now a dialysis position opened.

Should I apply being that I worked at my current unit less than 90 days? or switch to dayshift on my current floor? Should I stick it out? Part of me wants to quit because I don't feel like I can keep up with the acuity level and the temptation to fall asleep from 2-4am.