Navigating at night is just like diving at night before you have done it for the first time. INTIMIDATING !!
The navigation bit is easy. What is dificult is seing obstructions in the water like marker bouys, bits of flotsam etc. and, in a dificult sea, being able to "read" the water ahead.
However, that said, it is a beautiful experience especially on a moonlit night in a calm sea. You actualy learn a lot more about lights, bearings, conspic. features etc. which tend to be much less important during the day.
If you can, try it out by entering a busy, major harbour at night, and be amazed at all the navigation facilities put in place just for you, by the relevant authorities.
Try it. You will love it.