bigwul,I cannot say what is wrong with your Cocker(a breed I love),but I walk a Cocker every day for my neighbor,she is about the same age as yours.
If she had those symptoms,she would have been at the vet yesterday.
Please try to get your dog in as soon as possible,I do not think next week is good enough,if you explain the situation to your vet I am sure he'll see Zak right away.
Please keep us updated