Hello. welcome to HCM. It is common for many people to have sensation of heart beat (these are known as palpitations) at bedtime. This results in insomnia. Usually this happens when mind is worrying for something (family, children, self, occupation etc.... there are so many causes to worry in today s life) or is continuously in thought process. To some extent, it is natural for everybody. In your case, yoga will be of help as it will help you to be relaxed. Also, try avoiding day time naps and try reading some of your favorite light books at bedtime should help. A visit to your doctor and discussion regarding use of any anti-anxiety in mild doses can be helpful. Dont worry. Nothing is wrong with your brain. take care.