Brief Answer:
Can be congestive cardiac failure.

Detailed Answer:
Hello and Thanks for choosing"Ask a Doctor" service for your query,
Have seen your details,
The most important think in entire history which shifts diagnosis from respiratory to cardiac side is presence of swelling in feets.
Our lungs are connected to heart.When in old age heart becomes week it starts to throw back blood from heart into lungs.this causes accumulation of water in lungs hence breathing becomes difficult and cough is usually non productive.The excessive water begins to accumulate in your foot causing swelling.

As per protocol
you should go for
Pulmonary function test(to check lungs)
An 2d echo(to check heart)
And auscultaion and examination of heart and lung by a doctor. But as you have suggested that you have very limited medical access in your area i would suggest you to take tab Lasix(Furosamide) 40 mg in morning and 20 mg in evening for 5 days and tell me how you feel.This medicine would help to drain off excessive water from lungs.

Otherwise if you can then just follow the protocol as suggested above.

Hope i was helpful,
Follow ups are welcome.

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Brief Answer:
follow up.

Detailed Answer:

Hello again,
I am sorry but these are not over the counter.However you may get a prescription from any local doctor.
Hope i was helpful,
D rate the answer.

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