Hi
one finger typing as feeding sorry for mistakes in advance
i'm a GP
she may well have had a virus yesterday but its possible to have secondary bacterial infections on top - so things may have changes
essentially if you feel she is worse in any way - breathing faster - working harder to breathe (take her clothes off and look at her chest - is she sucking in very hard so her ribs stick out or does she appear to be sucking in the muscles at the bottom of the chest) is she feeding less etc. if so take her back to Gp today. they shouldn't mind and should have explained if things gets worse, she needs to be seen today.
not back on mumsnet for a while but hope that helps