My dog hasnt eaten or drink anything this whole day!!! PLZ HELP!?

he is 6 years old and he is a papillion except he is a runt. so he is very small only weighs 4 pounds. my brother said he hit him on the back of his head a little bit because he tried to bite him last night but this whole day he just layed in his kennel and didnt eat or drink anything and we dont want him to die of starvation because he is really tiny already! we already tried to hand feed him and hand water him(??) and he didnt even drink or eat! so please be mature about this and if u know whats going on or how to feed him and stuff like that so please help i need to know! thanks(: haha and yes i addded this question again becasue all the vets are closed and my mom doesnt want to go to the emergency vet clinic.