everyone wakes up hungry.
...or should for that matter.

waking up in the morning is a new day started. your body has disgested the foods you ate the night before, in the time while you slept.
maybe researching some body anatomy will do you good.

of course you should wake up hungry.. like the person said above, your body just finished digesting all the consumed food. did you used to not wake up hungry? in reality, you really should. that's why they call breakfast the most important meal of the day: your body just finished digesting all the food from last night and therefore needs new energy to start out a new day.