27 male 6’2 waking up middle of night with heart racing bad and sometimes sweating

Back in august I got into 2 car accident back to back in under 2 weeks for the most part I didn’t get injured at all and never really overthink about it Fast forward a month later ended up waking up for the first time with my heart racing felt like I was gonna pass out I rush to the hospital just for it to calm down and felt all jittery afterwards Doctors told me they didn’t see anything wrong with me and akgs and blood work came out fine as time passed I went back to the hospital another 5 times for same reason waking up middle of the night heart racing and still couldn’t find anything We are now in feb and still dealing with waking up in the middle of the night after an hour of sleeping notice my body changes starting to deal with ED which is frustrating seems like im more down and tired of feeling like this I’m new to all these feelings can’t make out if it’s a panic attack, anxiety, stress I’ve seen my doctor they did loads of test everything came out well I was pre diabetic before all of this but noticed I’m able to sleep in the couch sitting up right without waking up or hardly ever might do a sleep apnea test next but planning to change my diet and exercise to hopefully see progress on not waking up like this or dealing with this ED issue