It lasts no more than 5 minutes,but it's like internal shaking that seems to be somehow related to the heart. Or it may be the spine? Who the heck knows anymore. No it is not imaginary,as it has woken me up too.

As I said it has settled down alot when I started the COQ10. Getting anxious makes things worse.

You definately need to get it checked out by a doc who cares.