Brief Answer:
Bronchitis

Detailed Answer:
Hello

Thanks for the query

Bronchitis is usually the cause for dry cough which lasts for more than 3 weeks. Here is how you should go about it

1. Get a chest x ray done as soon as possible to rule out a chest infection
2. You will have to be treated with anti histaminincs and bronchodilators. If I were to be your doctor I would have prescribed Tab Montelukast with levocetrizine twice a day for a week
3. Avoid cold food and beverages
4. Keep yourself warm at all times


Dizziness and shortness of breath is often seen after a bout of cough, this is because of pooling of blood away from the heart due to increased pressure in the chest while coughing
I must add here that any cough lasting for more than 3 weeks should be evaluated and not left alone. Approach your doctor as soon as possible

I hope I was of help

I wish you good health and a speedy recovery

Regards

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