The average life span for a hamster is 1000 daysto the best of my knowledge. If he is getting to two years he's old butI have one nearing four, oldest I have ever heard of though. When theystart getting cranky, trying to bite, and just not themselves it isusually a sign that they are sick. The most likely illness for ahamster is called wet tail and it can come from stress, changing theirfood too quickly, or adding something to their diets.
Symptoms are tucked ears, wet bottoms, their eyes look dull or couldeven close, they bite, try to bury themselves, curl in a ball, and theexcrement is much smellier than normal. Does he have any ofthese signs?
Lisa