I also have the same thing, its as if my heart is racing, and I also get a fluttering feeling, mainly happens in the evening when I am resting, and also when I go to bed, I have had an ecg which was normal. I dont know whether its the diabetes or not, I also suffer terrible from night sweats, I seem to spend the whole night throwing the covers off, the sweat just pours from me, this has been happeing for quite some time now, I wish I could get it sorted. Good luck and let us know how things go.
Alison