Yes, pita = 18gram of carbs AND refried beans which are normally 23 grams of carbs for 1/2 cup. I eat canned refrieds all the time so I have it memorized.
The beans are fat free but never carb free. I love my beans but I will sometimes only have them if my BG is more on the low side to start out with.
Another alternative is that there are some low carb tortilla. Even a regular small taco shell is lower than the 18 carb pita.
I think maybe you just forgot about the beans when you did your count. 