Help with eating disorders!!!! plzz!!!!!?

im 14 years old and ive been bulimic for about 6 months. recently I went to the doctor and she said that I had to stop playing soccer because I lost 5 pounds in one week and it was dangerous for me to be playing sports. I don't think I'm unhealthy because I weigh a whopping 123 pounds and I'm 5'4. I think the doctor is taking this too seriously because it's not like I'm dangerously skinny or anything. is the doctor crazy or is it just me?