Did I speed my metabolism up? ?

Hey so I am 14, female, 5'5, and 94 lbs. I am recently recovering from anorexia. For about a month I ate 800 calories then for another month I ate 600 calories a day. I am now eating 2000 or more calories a day. I am exercising 5 days a week for 30 minutes. I am hungry all the time and haven't weighed myself in a week but I don't think I have gained weight. I look the same if not thinner. Did I speed up my metabolism? Also I haven't taken any laxatives but I have had diarrhea 2 this week. Yesterday I ate 3500 calories. But did number 2 like four times yesterday after I ate. My brother had a super fast metabolism before he went into highschool. Do I have that too?