Does anyone have intrusive thoughts about fainting. And think about your breathing too, or something like that?

Does anyone else struggle with OCD when it comes to breathing? I've had this for about two years now on and off and finally had enough and came on here to say this. When I try to explain this to other people, therapists, etc. they just don't get it, so maybe someone on here does. I literally cannot stop thinking about my breathing and when it is at its worst, the very act of breathing feels incredibly uncomfortable. It feels like the walls are closing in on me, I constantly feel like I'm having to catch my breath, and I constantly feel the urge to take a giant, "complete" breath and that is the only way I feel comfortable. It's usually manageable during the day, but at night when I try to go to sleep it's awful because when my brain has nothing else to focus on it reverts to the breathing. People tell me to just stop thinking about it but I literally cannot. Can anyone else relate or am I all alone on this one

does anyone else get really vivid intrusive thoughts of the person who you are talking to (or close to physically) just randomly striking you violently? i keep getting them when i’m just talking to my dad one on one in the car & i get a flash of intrusive thoughts of him grabbing my hair & shoving my face in the dashboard. it gets me so anxious :’)

Has anyone ever had an intrusive thought of thinking you’ve might’ve swallowed something dangerous and you can’t trust your own mind? And you feel like you need to go in to get checked out? Any advice or reassurance?