I am 60 yrs old, and have had issues with my blood pressure. It goes up and down. I only take a diuretic, no other meds except ibuprofen. Very often, when I lay down to rest, my heart beats really hard for a few minutes. I understand how these symptoms may be concerning. I encourage you to discuss this with your cardiologist, who can help determine the precise cause after a thorough, in-person evaluation. Many different factors affect your heart beat.