First as a former Nuke, congratulations and welcome to the club.
You are not a Nuke yet, you are in the training pipeline. The program has an actual documented 50% attrition rate. Are you going to be a knuckle dragger, twidget, or wire bitter?
Did you also volunteer for Submarines?
Being a Nuke is a lot like being a Marine, instant respect, and never lost. Once qualified you will always be a former Nuke not an ex Nuke.

As Dralore mentioned it is a very tough program. The 18 month Nuke school was as tough as my 4 year BS in Physics. At one point that pipeline was ranked #4 DEGREE program in the country for Nuclear Engineering. I consider it to be my Masters degree from a resume standpoint.

Again congratulations and good luck.