[Pebbles82]

Hamsters don’t really hibernate, they go into torpor - and that is when they get too cold. Torpor is quite dangerous and they often don’t come out of it again. So your hammy’s behaviour isn’t going to be that as it’s not cold. It sounds like she has moved her nest and hoard. They sometimes do this if their old nest is disturbed (eg during a clean out). Or it may be the heat (very likely). In hot weather they seek to cool off and can abandon the nest. If she is coming out less she is probably just a bit warm and lethargic. The swelling is something else. How old is she? If she’s not very old then she needs to see a vet as it could be an internal infection called Pyometra which needs fairly urgent treatment. It could still be that even if she is old but could be other things if she is getting old. Anyway swelling is usually a sign of something fairly serious that needs treatment (possibly antibiotics).

Could she have swallowed anything? Sometimes people are sold fluffy bedding for nesting and that can cause blockages so if you have any, that would be suspect (and best to bin it and use plain white toilet paper torn into strips).

Although it has been hot weather, her lethargy and behaviour could be due to illness or infection so she does need seeing by a vet. Best to see an exotic vet as they know more about hamster conditions (the cost is no different to any other vet). So google your nearest one. You’ll need a pet carrier with bedding and a little house in to take her in. You can get them quite cheap. A guinea pig sized one is best so there is room for a little house or hide. I also put a bit of food and cucumber in for hydration and hide the odd treat to keep them occupied in there.