usually if a snake refuses it's feed it's best to leave a few days I've found cause it saves on stress, then again I'm on a little bit of a different topic here more talking about snakes that refuse due to being move to a new enclosure or just plain wont' eat not change of food item. Usually if you try to offer straight away they just continue to refuse but if you give it a few days they tend to be more keen to have another go. Hope that helps, wasn't explained well sorry.
Allana