Squealing is usually a bad sign. It could be your hamster is angry, annoyed, scared or in pain. Check for illness or other possible causes. Gnawing constantly on the cage means that your hamster needs something to chew on, it is bored or stressed. If your hamster runs a lot stops , looks around frantically, ferociously grooms itself and keeps doing it, your hamster may be bored, stressed, wanting to exercise, anxious or flustered. Give him/her something to do and make sure there isn't anything stressing him or her out! Yawning and stretching is good. It means they are content or just had a very good sleep. Also you should always check on your hamster to make sure he/she is okay. Also, if your hamster starts showing any type of irregular behavior (coughing, sneezing, wheezing, walks hunched up, etc.), it could be sick. Make sure that if your hamster squeaks it means it is scared or wants to be alone.
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