Help me please,what is wrong with me?

i love my girlfriend so much ,i am a bi,and i am scared that i am going to lose her,because i never let her know how i am feeling,i am so quiet and i lie to her alot.i can actually speak with her and hold a long convesation only if i am lying or arguing about something silly,i never know how i am feeling.when she calls i don't answer the phone because i think i will be quiet and it will be awkward and i never call her,unless if i want to ask her something and it really sucks.i don't want her to see me outside of school ,we have been dating for a month now and she has never seen me outside of my school uniform and i don't want her to ,because i hate the shape of my body so much ,i can't go out of my house because of it ,i hate myself so much.the phone thing its not with her only ,even when my grandparents who misses me so much ,i am scared to answer and i miss them so much ,i can't visit them because i am scared my cousins that side will judge me,i am so uncomfortable with my body and i am so shy since childhood,do you think there is anything wrong with me,or i am just stupid