I can understand your teachers concern, with so much annorexia affecting teenage girls (and boys but less so). Im assuming your female?
They are simply looking our for you. It was my face and neck that lost its fat first and many people commented even though at that stage I hadnt lost a single pound! Your body changes shape before there is any sign of that on the scales.
They only need to see what you eat to know your eating plenty! Also, why would it be such a bad thing if they contacted your parents? I assume they know you've "gone Paleo?" If so, they know the amount of fatty meat you eat!
I wouldnt worry. You feel better and thats the main thing!
I'm not a complete idiot! There's parts missing!!