Hi.. Welcome to HEALTHCARE MAGIC.. As per our complain the insulin needle is a very small bore micro needle and needle prick injuries can not always be harmful or cause any symptoms like redness or swelling and as already 5 hours have passed then there is not necessary that she will have inflammatory symptoms and in case if delayed symptoms appear also they will be mild.. Other thing that I would like to tell you as an additional information that needle prick injuries can cause transmission of infection from the infected patients so it will be better if you get the information that the needle from which the patient was given insulin has any known infections. In case of no information a blood investigation of your wife can be carried out so that any risk of infection can be ruled out and if present initial control by medicines can be achieved.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.