Brief Answer:
Yes it could be serious

Detailed Answer:
Hi
Welcome To Ask A Doctor Service
I have gone through your question I understand your concern as you said you are having body ache and vomiting night sweats these all are constitutional symptoms and could be due to any type of body infection .

now as you said you are having vomiting it could be infection inside your abdomen so you need to get some basic routine test done like complete blood picture ultrasound abdomen and liver function test.
as you are having night sweats this could be due to tuberculosis or cardiac conditions so you should get one chest X-ray done and one ECG.

as I said there could be multiple conditions which can lead to the symptoms so yes it could be serious you should not take these symptoms lightly.

previously said that some lab test were done so if it is possible then kindly share those tests with me, so I could answer your query more appropriately I hope your query got answered.
thanks and regards
Dr diwashish

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