Laitka,

This is exactly how I felt and what I experienced during Induction. For me, like you, it only happens at night when I'm at rest. I feel fine--even great--during other times especially during vigorous cardio. Actually, I feel better immediately after excercise.

The only time I experience the palpitaitons are during the evenings after having exerted energy for physical activity. I'm not sure if it should be a concern, but I think you'd feel better at the very least if your doctor assured you after some tests and monitoring that nothing is amiss.