Advice from anorexics!?

anorexic for 2 and a half years i used to eat only honeydew cubers and vegetables i did not havea problem with leg swelling then suddenly when i started to add a little more fruit and vegetables also adding fiber one cereal 3 oz tilapia once a week , an egg white, or 1/4 cup barley ive been told it was due to being malnourished . other than that people in my life believe i look healthier how is it possible if im eating so little calories and it makes me scared i gained could it be due to hydration