I've had this a lot recently in the past couple years, I almost always can hear the thud of my heart beat when I lay down and it drives me nuts. Though my main cause of concern is if it is some sort of condition. Now, as far as I know I have no heart condition(no history of it either besides hbp) and my blood pressure is fairly low.(last time I checked was about a day ago with a bp of 107/either 63 or 73.) Does anyone know why this happens or if it is a common occurrence?