Why am I so embarrassed to go out with family?

my grandmother i love her to death, however she invited me to go to the mall with her tommorow and i'm not sure if i want to go just because i don't want to risk seeing any of the popular kids seeing me with my grandmother in a wheelchair (my grandma needs a wheelchair) Her having a wheelchair doesn't bother me.. its just all the attention of people looking at me its just embarrassing in a way? I am a 15 year old boy, is this normal or am I just a cold blooded evil person?