Grahamskye, obviously I'm not a medical professional, but I've had numerous conversations and tests with doctors over the last 7 years and been given lots of advice on what's worrying and what isn't. As you've had a number of normal ecg's I am confident to say that nothing else you're describing sounds too worrisome. Certainly the heart rate thing sounds normal to me, my heart rate at rest can fluctuate. I'm not sure about your head sensations, have you specifically mentioned these to a doctor? I'm not saying that because I'm worried, I simply don't know enough about those sorts of sensations. Still could be nothing to worry about but obviously get them checked out if you haven't. I wish you all the best.