My Cat keeps talking?

I have my cat for an entire year now and he is generally very quite. I tend to go out of town a lot so most of the time i go, he has a sitter. About 4 days ago i had to go to LA (i live in Oakland) and i couldn't find a sitter. So I gave him 4 bowls of food and water with a dispenser so he wont die. Anyways I came back this morning and he is fine, he hardly ate though, only one bowl and he normally eats a bowl in a day so ya. but he had water and food and everything was fine. But he keeps meowing now. Why? is he happy, is he hungry, what is up with him?