I need advice?

I went to the Dr about a week ago and she weighed me. She then called my mom into the room and we had a long chat, her saying she thought I was anorexic.
I am be no means anorexic, I eat alot whenever I get hungry but don't seem to put on much weight.
So could this be from being a vegan?

 

Were you around the same weight before you went vegan?

 

I accually gained a lil, but not too much.