Hi,
1) Go for 2 or 3 days and take a day off. Your body will need to heal.
2) The first day or two will be a real shock to the system (see Point #1)
3) If you can start the tour by adding a few miles each day, that will help.
4) You will be amazed at how heavy your bike is after you get all that crap on it.
5) Eventually you will throw some of your junk in a box and mail it home.