Halal food

"Is it halal?" she asked me while i was eating an imported chocolate. While battling with the urge to answer with sarcatism, i manage to reply with simple "Yes, it is halal".
I must be something wrong with me when ppl question what i eat/offer them is halal. Obviously, i wont eat or offered other muslims haram stuff. Am i too defensive that i feel like it's quite offensive when ppl asking on the halal status of the food that i eat of offer others?
Rule of thumb....or rule of my thumb
1) unless you really sure it is not halal, do not question the status of halal food other muslim offered or eat.
2) if you are still in doubt, dont eat or make a big fuss about not eating.