Of course you get a break, how ridiculous!
Obviously it would be a little odd if you scheduled your breaks with him beforehand, as if you were "clocking in/out" like the 9 to 5. That's just a little cold. But if you need an hour to check your email, call your dogsitter, whatever have you, it would be pretty overbearing of him to deny you. That said, the man will most likely need a break too. Rarely have I ever actually had to ask, but when my date mentions that he has something to do, I just ask him how long he'll be and if he minds if I run off for a bit, and give him a little privacy.
For just a 72 hour trip, I'm not sure how much time you would need. I really can't go without checking my email for more than 2 days, and the friend I leave my dog with for short trips likes to call at some point in the evening to fill me in on how much she's spoiling my furry little princess
~Mme X~