Brief Answer:
Gastroenteritis most likely

Detailed Answer:
Dear sir, I have gone through your question and I understand your concerns.

It seems that you are suffering from a gastroenteritis in reaction to an infection or a type of food that you are sensitive to.

I would recommend that you take metoclopramide (Primperan) 3 times daily to relieve nausea and vomiting. You should also make sure you are adequately hydrated with at least 8 cups daily of fluids to avoid dehydration from vomiting.

The chills could be due to elevated body temperature, so I would recommend that you measure your body temperature, if elevated you should take an antipyretic as Acetaminophen or Ibuprofen tablets. This will also relieve your body ache.

For itching, you can take an antihistaminic as Cetirizine 10mg once daily before going to bed.

I hope I answered your question.
Let me know if I can assist you further.
Regards

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