welcome to HCM!
I have read your question carefully and from my clinical experince I would say that this can be due to two things: heart problem or a panic attack
you ahve not mentioned that anything like this ever happened before, or if you are hypertensive/ diabetic, so, it is unlikely that it is due to some heart ailment, but to be on the safer side, had I been treating you, I would deficnitely go for and ECG, and X. Ray chest and check your BP.
If every thing turns out to be fine, this was a panic attack , and I would advice that you meet a psychiatrist
. Only after a good interview one can tell if you have some anxiety
problem or just an independent panic attack. For a person to ahve anxiety, it is not essential that there should be some stressors, one may have anxiety without any reason also. Till you see psychiatrist, you may take clonazepam
0.5 mg if you develop such attack.
Hope the reply helps you
feel free to ask more questions
Dr. Manisha Gopal