Thank you for your reply.
Vomiting and diarrhoea are non-specific clinical signs. This means they do not point towards a specific diagnosis, but they can be caused by a variety of conditions.
In Sadie’s case, possible differential diagnosis would include dietary indiscretion, infectious disease (such as viral gastroenteritis) or metabolic disease (such as pancreatitis, less likely). Also, a foreign body ingestion seems less likely (as they usually keep vomiting profusely), but at this stage it can't be ruled out completely.
As a general rule, if the vomit has settled and the energy levels are not too low you could monitor her, offering her often small amounts of water and a bland diet, such as chicken or white fish.
However, she will need to see a vet if she keeps vomiting or the energy levels decrease considerably or she is not interested in food and water at all. In this case, the vet will need to perform a full physical examination (and possibly further investigations, such as blood test and abdominal imaging) to rule out the potential underlying causes I listed above.
Does this make sense?