I am recovering from anorexia and I am scared to go back to school at the end of summer?

My friends knew I was anorexic because I wasn't eating anything. They didn't see me at my lowest weight because I was too sick to go to school and then I went to the hospital and then to treatment. I was in treatment for 3 1/2 months and they made me gain weight cause apparently being 13 and 55 pounds and 5'1 is unhealthy. I am now 5'3 and I weigh 98 pounds (yep i know i am very overweight). I am scared the people at school will think it's weird that I look different. I am scared they will think bad things about me. What should I do?