What Do Dizziness And Fluttering Sensation In The Chest Indicate?

Hi, for about a week now I have been experiencing my heart fluttering and lightheadedness, and the last three days it is increasing and now I am experiencing this about every 20-30 minutes. I had a physical a few months ago and everything was great. I am an african-american 55 yo female, 6ft, 230lbs. My cholesterol is excellent, but my blood pressure is borderline. I have no history of heart disease in my family. I do moderate exercise (walking). I should be taking Losartan HCTZ 100-25mg daily but I haven t been taking consistently for a while. I do have a history of being anemic and I have had these heart palpitation symptoms before--once it was because my potassium was very low and the other times I was anemic. I do have a doctor s appointment Thursday (regular checkup) but because this is now happening so frequently, I m not sure if I should wait or try to get an appointment tomorrow. I know some of the symptoms for heart attacks in women and not sure if I should be alarmed or not. Even in this short time of typing, my heart started racing again.