Brief Answer:
Nothing to be worried about

Detailed Answer:

Hello,

Any condition like cold, allergy, pneumonia etc that cause increased amount of sputum/phlegm production can result in such symptoms. If the sputum is swallowed rather than spitted out, then there is possibility of vomiting it up. If it occurred just once and she do not experience any other concerning symptoms, then there is nothing to be worried about. Please keep an eye on if she develops fever, shortness of breath, palpitations, further episodes of vomiting, diarrhea,confusion etc please be advised to follow up with the urgent care

Hope this answers your question
Please let me know if you need further clarification
Regards
Dr.Lekshmi

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