When I called the NR she was very sweet. She told me "I'm sorry I have no new information for you, they are still conducting interviews and you should hear by x date. I will call you when I have any information regarding the position." Then last week she called me and gave me an official job offer over the phone. She also thanked me for being so patient. I believe I had to wait so long because there were a number of NICU positions they were looking to fill so they could have a full class for orientation.
They may also be waiting to see if another more experienced candidate could fill the position.
I wouldn't freak out too much as these things often take time. After I interviewed I went over every answer I gave in my head and thought maybe I didn't do so well. I hope you get the job!!!