About a week ago I had a major panic attack. During it my heart started to beat very very hard and I could feel just how hard it was working, my heart seemed to work every hard. It lasted for 90 minutes. I started to sweat a lot during it. Since then I have no reoccurences, no palpitations or pain. The heart rate is normal and 70 or under at rest. But since it happened my heart seems to be beating very "hard". Each beat is much harder than normal. I can see it in my chest and when I lie down it's very noticable, I can feel it, it feels like my torso shakes when it beats and it's hard to sleep. I also have a very mild headache for some of the day. It hasn't changed in over a week. My doctor says everything seems normal and there is an ECG scheduled for next week. Is it just a hangover from the workout my heart got (I'm 3 stone overweight and rarely exercise unfortunately)? I 'm certain it's not purely psychological.