Brief Answer:
Need check up to differentiate in anemia, bronchitis, heart problem.

Detailed Answer:
HI XXXXX,
Thanks for the information.
Though there are many conditions causing breathlessness. But in my view Your breathlessness can be out of multiple causes -like anemia/ allergic bronchitis/ heart problem.
*Anemia is possible as in advanced age capacity to eat & digest is naturally diminished.
* Though you don't have known allergy or Asthma in past, I am including possibility of allergic bronchitis..( as you have little wheeze when you are breathless.) due to allergy (seems to be caused by wood dust created while sawing wood.) In my view this is the most possible cause. which needs a short medicinal course.. don't worry, you will be out of it soon.
* your palpitation & high blood pressure you have ,raise doubt of heart condition as a cause.. though palpitation ( raised heart rate ) can also be precipitated by anemia, psychological tension.
* In this context you need a primary through physical check up by your family physician.. He may carry out few investigations like-- blood Hb % , differential cell counts/auscultation of heart / X ray chest if necessary,and ECG / cardiac enzymes as per need.
a) He may advise a medicinal course for bronchitis ( antibiotic, anti allergic pills/ broncodilator oral/ injection /inhaled) or anemia ( Iron & nutritional supplements ) .
b) He may refer you to heart specialist/ chest physician/ hematologist for expert advise if he feels it necessary after checking you up.
* Please don't worry, this is the first episode of difficult breathing,you will be normal after a short course of medicines& following preventive care soon & will enjoy your planned tour!
I have tried to explain from all aspects. Hope you find it to be helpful & informative. Any follow up query is welcome.
Please grade the answer if you find it useful.
Thanks.

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