Palpitations give me trouble sleeping

[Jonas55]

I recently started having heart palpitations during the daytime i don't even notice but as soon as i lay down on the bed or try to sleep i can hear the beating and it bothers me too much. I went to the doctor and they said my heart is in good condition i also got checked for scoliosis they said it might cause abnormal heart beating but i don't have it.
I was wondering if it might be caused by my lungs ? and its my left lung working too fast and heart has nothing to do with it? the reason i thought about lungs was my spending lots of time indoors because of the pandemic.
Any similar experiences or advices ? everything is welcome