It's hard to say what causes the fast heart rate. For some reason, many of us have incidents that come and go for no apparent reason. Hormones do seems to play a role for many women, not sure why (but not surprising...lol).
Were you referred for any followup?
As for the leg cramping, that could be from the medication....is your doctor aware of the cramping? If you have not had an echocardiogram (ultrasound of the heart), it might not be a bad idea. The test does NOT assess the arteries, but it does provide results relative to the heart's chambers, walls, valves and function.
Thank you for your comments. I will pass the cramping onto the doc. I see him in another week or two for follow up. I have not had an echocardiogram yet, but have had the other screening done within the past 3 years. I appreciate any and all suggestions. Pattie