I'm ALWAYS hungry. is there something wrong with me?

i'm 16 and 108 pounds. i am always hungry.. and its not that whole thing where i eat just because i'm bored. i eat because i CONSTANTLY have a starving feeling in my stomach like i haven't eaten all day. and i eat meal after meal. like when i got to school today in the morning (7am) i brought last nights dinner (rice and beef). i ate that, and then at lunch i had pizza and a whole chicken caesar salad and then oreos and smart food and i was still not satisfied so i ate snacks during chemistry. and it is so weird because my mom and i ate dinner an hour ago. we had pasta and chicken. i felt satisfied but fifteen minutes later i began to have this feeling in my stomach like i havent eaten in forever. i dont think its normal because my friends always make fun of me for eating so much..idk i think theres something wrong with me haha