Hibernating Hamster

Question
I believe Hammy is hibernating (or sick) he is cold and doesn't move much, he seems to have a puffy belly. I've tried to warm him up but nothing works. He is only 14mo old and has been very active up until 3 days ago. The weather here is very cold. Is there a way to warm a terrarium? What do you think?  

Answer
i think your hamster is sick and has a serious problem with his stomach if it's bloated.he more than likely needs antibiotics because he probably has an infection. if he's not eating and drinking he is more than likely sick. hamsters can deal with cooler temperatures so I really don't think he's hibernating.