Brief Answer:
Specialist's help to find the cause & advise / self help would help.

Detailed Answer:
Hi,XXXX,
Thanks for the query. I have read your query carefully & I understand your concern .
* The cause of your problem in my view can be-
1. Sleep apnea.. this causes inability to breathe while sleeping .. causing low oxygen in body, dizziness, & fatigue ( physical, psychological.) The resulting fear & psychological stress generated can lead to nightmare sort of symptoms
Apnea can occur due to any obstruction in breathing passage during sleep ( family history/ENT problem/ Dental problems/neurological problems.
2. Night mare.. It is an unpleasant dream, that causes strong emotional response in mind . This leads to mainly fear, anxiety, despair & sadness.
This condition is specifically seen when a person leads a fearful life with lot of stress & tension./ chronic illness/ sleep apnea.
* In this context I would consult to consult your family physician for primary investigations to have a through general review of your health issues( specially, any chronic health problem/ ENT /dental ) & then refer you to sleep specialist/ ENT specialist/ dentist/ psychiatrist/ counselor as per the impression he gets.
- After pin pointing the cause you will be given specified treatment to relieve your symptoms .
* self help-
-A healthy lifestyle ( healthy eating/ exercises Yoga, walk, mind concentration) / positive thinking
- Avoid things that relax the throat muscles like sleeping pills/ alcohol.,
- Specific exercises advised by a physiotherapist to strengthen the throat muscles.
- Try to be tension free with help of a counselor/ with yoganidra audio CD.
- Make a habit to sleep on side.
Thus a systematic assessment of the cause & methodical & persistent treatment with self help.. you would definitely get rid of the fearful symptoms you have.
I hope you find the answer both informative as well as helpful in finding the solution of your problem. Any follow up query is welcome.
Thanks.

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