I think at the ripe old age of 46 I have actually come to terms with the fact that I do. What was me just thinking was low self esteem about myself for years, I think its more than that, when I had to stand at the front of my gym class as the back was full (I was late and have my spot at the back so I cant see into the mirror), and as I had to stand in the front, I couldn't do the class, I felt sick and left half way through. I do have a mirror at home, I couldn't never stand there and look at myself, just a quick once over to see if what I am wearing matches, and the close the door. I don't like what I see, I see all the flaws, there isn't one part of me that I would tell you I liked if you had to ask me. I am underweight too, hit me now on my birthday later this month, I weigh the same as my age.
If you can relate, what did you do about it. Did you speak to someone, do something (I thought if I stood in front of the mirror each day, a little bit longer each day..something might happen). I have a teenage daughter, she is really confident, but the thing that worries me is if she picks up on my issue (which I thought was a non issue really).
I hope you're still checking for updates on this post. I have an still do suffer from body dysmorphia and I would give you the opposite advise. Don't look in the mirror, the mirror is not your friend and what you're seeing isn't real. I'm saying this as much to myself as I am to you.