Am I underweight?

Am I? I am a 13 year old manly, and I am 5ft 8in and 101 lb. I do NOT starve myself, throw up after eating (eww...) or diet. Acctually, I guzzle alot more than my friends, who are all around my rank and weigh more than me. So, am I underweight? Same here man, i eat mcdonalds/pizza every darkness and yet i dont gain shlt! I devise its got something to do beside my digestive system. I currently trying some weight gain.
very well if u are reeally really skinny that u see your skin then explicitly unhealthy. But if your typical then that manner you have a hurriedly tabilism witch means your body digest quiker than others. Witch finances ur fine just don't verbs