Brief Answer:
Anxiety and Panic Attacks

Detailed Answer:
Thank you for asking
COnsidering your young age and no previous history of any cardiac or vascular history , i think this sudden barrage of symptoms hardly remaining for a few minutes and self resolving is most likely an anxiety and psychiatric issue and doe snot seem like an organic one.
Anxiety and stress can cause migraines headaches and they may present as numbness, palpitations are also psychological and anxiety related.
Let me discuss some other odds.
Providing your history your labs are clear like EKG and echo etc so that clears the cardiac issue.
Now assessing thyroid functions would be wise to rule out any metabolic issue like hyperthyroidism as that may cause this palipitation.
GERD / Acid reflux may also cause this and if any Gi symtom of GERD then that needs to be addressed and may resolve the symptom.
Sudden cold hands and extremities are classic for anxiety but to be on the safer road and assess the vascular status and rule out any hyperactive sympathetic functioning troubles like raynaurd's phenomenon would be wise , More if the symptoms are after exposure to cold etc.
Smoking itself may cause such cold extremities, so quitting that would be wise.
I will repeat, to me its a psychiatric profile and anxiety and panic attacks are the only valid explanation for connecting all the symptoms, but there is no harm to get evaluated for any trouble which i would say is least likely to show any positive finding.
Get GERD and Migraine Prophylaxis meanwhile and see if it helps.
I hope it helps.
Take good care of yourself and dont forget to close the discussion please.
may the odds be ever in your favour.
Regards
Khan

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