Hello

Thanks for the query

The condition looks more like food poisoning than stomach flu more so because he does not have fever or stomach pain.The mucus he vomited could be the mucus he has swallowed as children tend to do that

The second issue is he has rhinitis and a possible sinusitis.

This can be handled well if he can do steam inhalations,3 times a day
But since your child is small please try this only if you are confident and never it should be done unsupervised.

Antihistaminics also help, like levocetrizine, it helps to stop the nasal discharge and the yellow mucus, please XXXXXXX your doctor for a prescription

I advice you to do the following

1. Feed him a liquid diet first like plain water, fresh juice which is not sour, if he tolerates that try soft bland food
2. Avoid milk and milk products
3. In one litre of clean water add a pich of salt and 2 spoons of sugar,make him drink it sip by sip. This will prevent deydration
4. If he continues to vomit please take him to the pediatrician
5. Watch out for diarrhea and fever
6. Antibiotics need not be started until he develops fever

Children have a higher metabolic rate and also they run around and are more active than adults, they tend to drink more water, which is a healthy habit.
Make sure the water he drinks is clean, boiled and cooled water would be ideal

Constant swallowing looks like a behavioral issue more than a pathological one. Many children have these like picking of nose, make sounds like 'tick tick', you can ignore them as they tend to fade away with age

I am not able to diagnose the purplish circles under his eyes. Kindly attach a photo if you can so that I can come to a conlcusion.

I hope I have answered to your query, if there are no further queries please accept my answer

I wish your son a speedy recovery

Regards

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