Re: Suffocating feeling when lying down.
Sounds possible. Are you overweight at all? Gasping in the night can be sleep apnoea but I think that's quite unlikely if it's happening in the day as well.
"A physical element" is often a huge part of anxiety, and you are probably aware that you are describing hyperventilation, which can cause many physical symptoms.
I don't know you so don't know your history, are you on meds? Have they been reviewed recently? Are you going to speak to your doctor about this? (I would if I were you, for reassurance).
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