I had non-serious palpitations for many years (wore 24 to 48 hrs holter monitors). Then, about three years ago, in my early 60's the palpitations were much more frequent and much more troublesome. A 72 hr holter monitor picked up both atrial tachycardia (annoying but not life threatening) and the concerning and must be treated non-sustained ventricular tachycardia. That is now under control with 12.5mg of metoprolol twice a day.
Never good to assume palpitations are nothing to worry about.