Palpitations, especially if accompanied by a hot flash, are very common. This phenomenon is usually caused by adrenal stress and can often be helped by stress relieving herbs such as Passion flower or Avena sativa. However, if you are concerned by this, then it is best just to get your symptoms checked out by your doctor for peace of mind.
You could also try sage tablets for the hot flashes.
Disturbed sleep can result in fatigue, which may be a factor of the palpitations, so it can become a vicious circle. Stay well hydrated too, because palpitations worsen when you are dehydrated.