Thanks for your question on Healthcare Magic.
I can understand your concern.
Tiredness, breathlessness and headache in young (27 years) individual can be due to
hypertension, other heart diseases and asthma.. So better to
consult cardiologist and get done blood pressure monitoring, ecg and 2d echo.
Consult pulmonologist and get done clinical examination of respiratory system and PFT (pulmonary function test).
If all these are normal then no need to worry for major heart and lung related diseases.
Sometimes, undiagnosed stress and anxiety can cause similar symptoms.
So better to
consult psychiatrist and get done
counselling sessions. Try to identify stressor in your life and start working on it's solution.
You may need anxiolytic drugs too.
Don't worry, you will be alright.
Avoid stress and tension, be relax and calm.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.