These things are specific to your employer, both the pay scale and the transferring. Some places won't allow you to transfer so soon, and some places may knock your pay back when you transfer into a new specialty ...especially if it's a desirable and competitive specialty.
As a new graduate in Texas 10 years ago, I was automatically given a $5(something) hourly increase and promoted to "Nurse II" after two years. It was at that point that they didn't want to lose us to other hospitals. As someone just exiting a new graduate program, you might not have much leverage yet.
When is your first performance review? That might be a good time to explore the subject, especially if they have good things to say about you. I agree that asking HR what typically happens might also be a good idea.
