Thanks for all these additional information.
I understand your concern.
Well as you describe,possible cause may include Gastroenteritis.
And you should hydrate yourself with gatorade first.
Avoid pear,apple and take only banana.
You should try yogurt and toast,boiled rice in small amount.
Take OTC Emetrol for nausea and vomiting.
Also take OTC Zantac 150 mg after meals.
You should try Mylanta gas and metamucil.
Also start a probiotic which regulates your gut flora.
Monitor your blood pressure also.
Take proper rest.
Also post nasal drip can be caused due to acid reflux so you should try saline gargles.
If you 'll be unable to keep liquids down then see a doctor ASAP for prompt management.
Let me know if you have any further query so we can discuss it thoroughly in every aspect.
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