How should I respond to this?

Within the past 6 months i've had some 'not eating' issues (ive never been diagnosed with an e.d.) my friends know this bcuz i wasnt eatin lunch. Today i was in my yearbook class and two if my bffs were talkin. One said she had forgotten her lunch for two days but someone had given her a lunch. Then my other friend shoited to her across the room saying "you need to eat! Dont turn into *she shouts my name*" - my entire class heard. When my friend heard my other friend shout this she ran iver to me got close to nt face. Put her hand on both sides of my head and whispered quickly "dont let it bother you. Dont listen to it." ... Im not sure how i should respOnd to my friend who knows i struggle an shoute it across the classroom.