I'm not too sure if it's common but the anxiety does play a big role in appetite. I had the same thing happen to me. I am 5'0 and I went from 110 to 97 pounds! And I am known to finish my food and someone else's but I just don't eat like I used to anymore only small things now. When I found that out I cried because I haven't been that small since I was younger. I would definitely go see the doctor to make sure nothing else it going on. I also suffer from GERD as well and they both don't mix. Best wishes to you.