Yes for me this goes on for several hours. Probably adrenaline rush for you, I also wonder if it’s a sudden wake from deep sleep? That would also trigger an adrenaline response but not sure why you’d suddenly wake from deep sleep?
UGH that was me this morning. I had one of those nights where you wake up and can't sleep for hours. I fell back to sleep around 5am-ish. When I was into a deep, deep, deep sleep, hubby touched my arm or said my name or both. I was pulled out of this dream. I didn't know what was happening, like coming out of anesthesia, but I heard weird vibration noises/feeling and realized it was coming from my chest. I put my finger to my neck and the pulse was racing so fast like never before. Scary scary. I started to wake up but was groggy and panicked all at the same time. I was definitely scared I might be in some kind of arrythmia that may or may not right itself. Today has been tough with exhaustion. Have to admit I'm a little nervous about going to sleep tonight.
Long winded story to say I get that adrenaline response when suddenly woken from deep sleep too. It has happened several times.