Possible panic attacks?

I have had a lot of stress lately and I have had panic attacks before. I have noticed that for the past 3 nights, I have woken up with my heart pounding out of my chest, but the crazy thing is, I check my apical pulse and its normal :/ My breathing rate is normal, I’m not sure what is causing this crazy fast pace heart rate feeling in my chest. Its not when I’m completely asleep, just about 30 minutes after laying down. I’m not really thinking about anything but is it possible that I am still thinking about things in the back of my mind that are stressing me out?

Maybe That can be the reason or it can be something else I’m no doctor but you maybe should consider going to see one