Weird shock feeling in heart/chest

Last night when I was asleep I was woken up by a shock feeling I felt in my heart. I was in deep sleep and woke up because the feeling was so scary. It felt like an electric shock. I fell right back asleep and haven’t felt that feeling since then.

I went to sleep very stressed that night because I was worried about my Covid symptoms getting worse and in general was having stress due to having Covid.

I keep checking my oxygen and heart rate levels, everything is perfect. My heart BPM is usually around 88 and my oxygen bounces between 98 and 99. Therefore I’m thinking the heart shock feeling was probably due to stress? Because otherwise wouldn’t something be abnormal with either my oxygen level or heart beat?

I called a doctor today and they told me to just keep monitoring it because as of right now I seem fine plus I have perfect vital signs.

I forgot to mention, I’ve had weird heart feelings (fluttering, weird feelings in general) ever since I got my first dose of Pfizer. Not sure if it plays a role. I can’t find anything online to match my symptom except for cardiogenic shock but that’s definitely not what I had. I’m thinking arrhythmia?

Think it’s something serious? I can’t sleep because I’m terrified! I have an appointment with another doctor tomorrow, I’ll definitely let her know. I just want some sleep tonight.