We share some things in common, so I can relate to your post - such as preferring to sleep 10pm to 6-7a; having never worked nights before; being a new grad slated to work nights.
First, being a new grad, you won't be bored on nights for a while. It will take a while to get adjusted to the new routine. At my hospital, we have 8 patients on night shift (6 on days), and have more paperwork on nights.
I've only been on nights for a few weeks - was scared 'bout changing my sleep routine but was able to do it. There are many other threads here regarding suggestions on how to adjust your sleeping routine for nights... find those and use the suggestions that you think will work for you.
The true reality of working nights (just my opinion) is you're not working just 3 days (nights) - you're working 5. Why, because you have to spend the day before and the day after adjusting your sleep patterns.
On a positive note (others here have mentioned this), you get to spend more quality time with your patients (not always, but sometimes).
Congratulations on passing NCLEX and your new job. You can do it.