Brief Answer:
Seems like an anxiety attack

Detailed Answer:
Hello,
Thank you for using HCM to post your question.

I read it carefully.
Seems like you are having an anxiety attack.
You need to calm down, because you are young and its very, very unlikely for you to happen something in that way, during your sleep.

-- Get out of your window and breath little fresh air. -- You can also breath into a paperbag. It will help you with some symptoms.
-- You should start adressing the stressful factors that are causing your anxiety symptoms.
-- Start physical activity, running in the mornings or gym. That has proven to help a lot.
-- Find someone, a good friend and talk with him/her about problems that you think about
-- Find activities that you like to do, and persuade them.

All these mentioned above are helpful advises. If these episodes continue despite all those, you will need to see a local doctor who can prescribe you the needed medicines.

Hope this is helpful
Let me know if you need more clarifications

Take care

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Brief Answer:
Explained some causes of anxiety symptoms

Detailed Answer:
Hello,

Thank you for your follow-up question.

Since the symptom you are describing, and the fact that you have this fear not based on physical findings, it is typical of an anxiety/panic attack. Also the fact that is happening more during night, waking you up from sleep, the chest tightness, you age (unless you are diagnosed since childhood with any heart problem) ect...all are symptoms that suggest it.

Anxiety happens to sensitive people, people who have had a loss in family/friendship the last 6 months, going through difficult/stressful situations recently, sometimes it may come out of nowhere if the symptoms are there but no physical/organic evidence of a problem exists, or if you have family or past history of mental health problems

Let me know how can I help you further. Otherwise please close and rate the answer.

Regards,

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