I worked compressed weekends (16 hours Sat & Sun) as an LVN (NeuroTrauma StepDown) for 2 years while completing my BSN. It was only later on that I realized I had gone a full 24 months without more than the occasional single day off. I did this in my mid 20's, with 2 pre-school kids & a wonderfully supportive full-time hubby. It worked for me. Your mileage may vary.
Cutting my hours helped balance me out. I still work pretty much every day but I went from 10+ hour days 5 days a week the first 10 months of nursing school to 20 hours a week now. You should be ok as long as you balance the time that you are off. Only you know your work ethic and what's doable for you before becoming burnt out. Make sure your off/class/clinical days are used for studying and whatever rest you can get and I pray you'll be just fine! Congratulations and good luck