I've Been Having A Weird Thing Happening For A Few

I've been having a weird thing happening for a few days now. It scares me. I am on blood pressure and cholesterol meds for a year now. I feel my heart beating funny and fast... sometimes I think it's missing a beat and I feel light headed a little then it subsides. I just noticed a small bald spots today on my head the size of a dime. I'm a 56 year old female. My parents have had heart conditionsurgery and I believe I've had some added stress lately. I've actually had steps most of my life but usually handle it well.