I can't breathe

I'm scared of the fact that maybe one day Ill stop breathing taking my last breath I can't scream I can't breathe I can't catch my breath it feels like Im in water by someone holding me down under until my last breath with water feeling my lungs and theirs nothing left of me it feels like something is tugging me back from trying to cope with my pain trying to take me where I was before not letting me go to were I need to be letting my pain go leaving everything and everyone behind so I can cope with the pain I have surrounding my heart making my chest get tight and tense instead of letting me be calm it gives me rage