it's just the healing process - your body is now AWARE that there isn't any more alcohol coming IN, so it has to make adjustments. BIG ones.
did you ever see the movie What's Up Doc with Barb Streisand and Ryan O'Neal with the car chase scene where everybody kept driving thru the fresh cement??? every time the worker would get it all smoothed out, another car would come flying thru messing it all up again. til finally the cement guy just gives up. that's kind of how our body feels when we keep mucking up the process.....
see at about 2.1 of video:
https://www.youtube.com/watch?v=abYamYSx9o4