Whats wrong with my puppy?

I hav 2 chihuahua mixes tht are from thr same breed but today one of them is acting wierd. His nose isnt wet, he is shaking wen he stands, he looks a lil dehydrated, disoriented, and he just lays down and stays there...... hes usually very hyper and jumpy.... we cant tak him to the vet because its not opened today.... is there anything i can do to help him??