I am a server, and it really sucks when a person says "I can't have gluten". Please be ready to explain what gluten or lactose IS. In the USA, most restaurant staff is Hispanic- with very little English, and communicating is hard. Also, we may have one guy making the soups, another making entrees, another making salads & dressings. So chasing down all this information is taking time away from my other tables. It would REALLY help if you went to an online menu & got an idea of what we serve before you come in.
While I totally sympathize with your plight, I can't be responsible for all dietary needs. But I will help as much as I can.