Totally normal!
Day 13, congratulations!
Here's the thing; you've been medicating your body and your mind.
What you're going to experience is a 'rebalancing' period and that is going to mess with you - physically, emotionally, mentally, spiritually. This does taper off and eventually begins to head nowhere but UP.
Along the way, be patient with yourself and remind yourself every day that it took a long time for your body and mind and emotions and mental processes and sense of self to become pickled in booze..... so it's also going to take time for all of that to cleanse and become healthy again.
You can help out the process by focusing on very good, healthy nutrition, water intake, cleansing teas, exercise, meditation and spiritually-nourishing pursuits.
Hang in there, this is just the beginning. It's a struggle at first but it becomes AWESOME.