Hi! You have full rights to be concerned with what you have experienced. First you need to understand that alcohol causes problems with the sleep architecture and you sometimes feel that you are awake or "on surface" as you have described even though you are sleeping. Its better that you have undergone an EKG and the fact that it has come out normal, spares you a lot of concerns. There could be a hypoglycemic episode under the influence of alcohol, but then it is mostly reversible. If alcohol is causing you so much trouble, why bot consider leaving it for all. Afterall its not essential to live. And not forget you have anxiety
disorders and alcohol will do more bad than any good to you.
Hope i could satisfy your concerns. The things should be fine and nothing much to worry about.