Joan,
Do not let the Departure Anxiety get to you.
You have used the unit before - Correct?
(If no, spend at least one night in the driveway at home, and then hook up the unit and take to an empty industrial parking lot and practice parking and such.
If you are worried, make lists. What you need to bring as far as food and clothing. Remember, you aren't driving off the end of the earth. There are stores in NC where you can buy things and you don't even have to get you money changed.
I would advise that you try to end the first day south of DC. There is friendly place called Falmouth. If you have water in the tank and the battery charged, you won't need a campground. Just a quiet flat place. That will be easier to find south of DC, but you still won't be out of the megapolis.
Enjoy the excursion.
Matt