Hello. I Am 42. I Have This Strange Thing I'm

Hello. I am 42. I have this strange thing I'm dealing with. I will be laying down about to doze off or just watching a movie and I get a rapid heart beat and a weird taste in my mouth. I was born with a heart murmur which the doctors checked and told me its nothing to worry about. I never got heart paps til recently. It scares me because I can hear it beating fast and will have to sit up in bed and breathe in and out. I can always tell when its beating fast and when it slows down. The doctor says maybe its too much soda or coffee leading to anxiety. I am a smoker. What's your take on this because if smoking is the issue I will quit