I m female 25, 5 2 , 170lb. Have a history of tachycardia & panic attacks. Two nights ago I was doing laundry and all of a sudden got hot, shaky, weak, my heart started racing and I had a prickly feeling in my skin. I had eaten & drank well that day. I woke up yesterday feeling the same. Went to work thinking it would go away but it didn t, so I came home. I didn t have much of an appetite yesterday. Woke up today and felt the same again. It s not anything like panic attacks though. It s a completely different feeling.