I went to the doctor today for several issues. I am a 31 year old female.I have been having pains in my chest for about 2 months now. Basically, at random times my heart feels like it is going beat out of my chest. It becomes painful. It is worse when I try to do exercise. I have been gaining an excessive amount of weight, and cannot seem to get it off with a healthy diet, or exercise. I am extremely exhausted and feel tired and run down every day, no matter how well I sleep. I get headaches, lightheaded, and my stomach cramps after I eat. While at the doctor, she took an EKG, and said that I have a sinus arrhythmia, that could be cause by an underlining issue such as hypothyroidism. However, until my blood work is back in two weeks she will be putting me on a medication called atenolol 25 mg tablets one time daily, she also called in a beta blocker. I have never taken a medication like this in my life, and have always been pretty healthy up until recently. I am concerned about taking this medication because it is for my heart. should I be worried, and get a second opinion or take the medication?