Why am I suddenly hyper aware of my heartbeat and anxious about it?

Hi all. Just wondering, I guess it's anxiety, who of you have experienced just a sudden feeling of fear for no apparent reason, like this uneasy feeling like you're scared but there's no reason and then your mind starts racing and searches for why you feel like this and all kind of bizzare stuff pops up. ?

Don’t mind me just riding out a massive anxiety attack after a few rough weeks of actual health issues. I have major health anxiety and I’ve had 2 awful asthma attacks recently due to wildfire smoke coming into our area. I hate having asthma because I didn’t know I had it for so long. And I never really know if my shortness of breath is anxiety or asthma 😭😩 It freaks me out whenever I have to get treatment for it because they always run an EKG to make sure my heart is fine. After having COVID last year (then getting the vaccination) one of my new anxieties is developing random blood clots despite being physically healthy. I go on Twitter for the memes then the next second I’ll see someone’s personal story about how someone they knew dropped dead randomly from the shot. It freaks me out so bad. Like what?? I don’t want to stop using Twitter either because I like it and don’t want to avoid any triggers. Back to health, they took an X-ray of my lungs the other day as a part of protocol because I couldn’t breathe that well (because I was having an asthma attack 😩) and it freaked me out so bad. Everything came back clear but my discharge papers said to get my heart checked out just in case. My resting heart rate is generally higher because of anxiety anywhere from 75-85. I hate having health anxiety on top of actual health problems. My doctors tell me I’m healthy despite asthma and allergies. Every day is a battle with health anxiety. Sometimes I can’t even workout because I’m so focused on my heart rate or breathing. Like I’m genuinely convinced I’ll die of a random disease I don’t know I have. AnywAY, health anxiety OCD is something I’ve had since I had my first panic attack. As most of you know that anxiety can manifest itself in so many ways it’s horrifying sometimes. Hopefully I feel better again soon bc this ain’t it chief!! 🥺

I went to the hospital Sunday night because I had a racing/pounding heart.. it woke me up from a dead sleep. I thought I was having a heart attack. My partner put their hand over my chest and could feel how fast it was pounding and they got up from a dead sleep to take me to the hospital. I was so confused when they tests came back normal. I think I just had another episode. I got this intense fear that I was going to act out or harm myself. I then felt derealization and an intense anxiety. I almost called 911 on myself. I’ve had small episodes like this before but these last 2 have been super intense. Anyone else experience this?