As her temperature was above 100.4, then there is a possibility that this is H1N1 but this does not mean that she should go to ER if she is otherwise well (no diabetes, pregnancy, asthma etc). Most young adults cope with the H1N1 infection in the same way as any flu and she should be feeling better in another few days. There is some debate about whether tamiflu should be started however I have seen many patients experience diarrhea and abdominal pain with the tamiflu so it may not be ideal for your daughter.

Without a swab for PCR then it is not possible to confirm that this is H1N1 and it may be a gastro-enteritis. The color of stool and lack of blood mean that this is also less worrying.

As long as she is managing to continue to drink fluid and pass urine then I would be reluctant to suggest ER, however many family doctors are happy to discuss things on the phone. Do not visit your practice without phoning first to avoid spreading the infection.

Do make sure that she stays away from kitchen, and everyone in the house must employ excellent hand hygiene habits.

The only thing of concern is that her fever has not come down. Ensure that she is taking acetaminophen or ibuprofen regularly. If the fever does not respond to two further doses, and luke-warm sponge down then I would contact a doctor for advice about the protocol in your area.