I am a snob? ???? ?

I'm 16. i have acknowledged the fact that i seem snobby,and i want to change.my now friend told me when she first met me she thought i was a snob. guys are afraid to approach me.only when im with my friends do they ever approach.my grandma told me that guys can sense my "don't touch me,uppity,snobby manner".i was shocked when she told me this because : she is not a guy, and, she is not with me when i am around guys. she's right though..it shocked me though and made me feel i need to change. i am a very very very nice person,once people get to know me they know i am not a snob at all.i can be shy around new people. this is really affecting me because there is one boy at school, who is always looking at me,but i pretend i dont notice him because i guess im shy and nervous and play hard to get? i think this is why he hasn't approached me,but i know he likes me. i really dont know whats wrong with me people alway s think im some kind of snob when really i really dont want to be known as this and i dont know why i seem like such a snobby person. guys hardly approach me but people are always telling me im pretty,maybe that is why it got to my head and im snobbish? i really dont know and i am in desperate need of help i desperately want to change and not seem snobbish. help me?