Hello,
Thanks for the query.
It seems you might have regurgitated stomach acid along with the food.
This acid might have caused some local inflammation,which should settle soon of it's own.
I don't think any particular treatment is required at the moment.
Please do get to me if any further assistance is required on this issue.
Best of luck
Thanks

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 Hello,
You are absolutely right.  In unusual situations, food particles may make their way into the sinus cavities and may cause infection when left untreated. Flushing the sinuses is a fairly simple task and you can do it with a NETI pot.

Mix the salt and water until the salt has completely dissolved. Pour this solution into the neti pot.

Stand in front of a sink and tilt the head to the side, with one nostril facing upward. Place the nozzle of the neti pot in the upwards facing nostril and slowly pour in the solution. Pour half of this through the nostril, letting the flow drip through the downward-facing nostril.

Tilt the head in the opposite direction and pour the remainder of the solution through the other nostril in the same manner. 
Blow the nose in a tissue to release any solution and loose particles and fluids from the nasal cavity. Breath in and out to determine if the food has indeed been flushed out. If there is still some obstruction in the air flow, mix another solution and repeat the entire process.

I hope you can resolve you problem this way.
Thanks

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