How To Tell If Kitten Is Dehydrated?

my kitten is only 1 month old and she has been sick for 4 days. She has a high fever, can’t eat or drink anything without throwing up. Her eyes are blood shot, her gums are pale white and look like they could be bleeding. What do I do? Is there something i can give her to make it better? It’s very important that she gets better—I don’t know what else to do!