Yes, I agree. Try to eat a little and hopefully they have one of those chairs in his room that you can take short naps in. You need to keep your strength up.
I would wash my face with cool water. It would make me feel refreshed. Read, look at decor magazines, or crochet to keep your mind occupied between doctor visits. He knows that you are there. Sometimes soft music that he likes, holding his hand, and gently assuring him with your voice have healing qualities.
Our prayers are with you and Hubs for strength and healing.