I get this, sometimes its low, sometimes high. I dont think a slow heart rate is anything to worry about, although it is a common anxiety symptom. Like my mum always told me, the slower the better, and its true because your heart is not having to work very hard to pump blood round the body, which is a good thing, kinda saying your pretty healthy. I think it can also mean normal blood pressure, wich is another good thing.

Hope this helps,

james