Hello and welcome. Thank you for requesting me. I'm sorry to hear your new hamster has developed these symptoms.It sounds like your hamster has a respiratory infection, similar to colds or the flu. These illnesses are more serious in hamsters than in people because they can rapidly lead to complications and death in hamsters.
There isn't a lot you can do on your own. Keep your hamster warm. Make sure the litter you are using doesn't contain cedar or pine. Paper-based beddings are best. The best thing you can do is make an appointment with a vet. That way, you'll get a definite diagnosis and proper treatment. To read more about colds and flu in hamsters, check this link:
If your hamster isn't eating, you can also make a mixture of half milk, half water, and a little honey. Warm it a bit, and feed it to your hamster. If she won't drink it, you can put a little at a time into the side of her mouth through a syringe. Don't put it straight down the throat because it can be aspirated into the lungs that way. If you have a vaporizer or nebulizer, you can use that in her room to make it easier for her to breathe. These are all supportive measures, and don't take the place of a visit to a vet.
The following links will take you to directories of vets who treat small rodents. At the first site, you'll come to a log-in page. Sign in as 'member' and use 'member' as your password ***** well.
If the pet store has a one week guarantee, another option would be to return the hamster. Many people get too attached right away to be able to do that, but it may be a choice. I wish I could give you an effective home remedy, but I believe you deserve honesty. There is no home remedy for such infections. Without treatment, they usually progress to pneumonia, which is life threatening.
If you have more questions, let me know in a REPLY. I hope your hamster will reach a full recovery.
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