I am fostering a tiny kitten (3 weeks old) that has not been able to hold down his food for the last couple feedings. He is very lethargic and has a dry nose. Yesterday he was perfectly fine. I thought he might be dehydrated so I gave him pedialyte and I also put some sugar water on his gums in case of hypoglycemia. He's not moving very much and his heartbeat seems to be slow and harder to hear compared to his siblings. Although he had a small well-formed bowel movement and urinated a little. Since I cannot get to a vet until tomorrow, I was wondering if there is anything else that I should be doing and how often I should be doing it in this very time sensitive situation. Thank you.