Is my hamster homesick?

Recently i've been on holiday and had my bezzie mate to look after him for me. She did a good job but my hamster bit her on the last day, just randomly, her mum aswel got bitten but the hamster was fine with her dad! when we brought him to my nans he looked like he was dying, because he was drooping and not moving ver much. Please help! is he just homesick?