Ok, i don't know why but im this dark, morbid person that's scared to buy dark clothes. Help me...?

I dunno, guess im afraid people'll laugh at me and call me a poser. But seriously, i don't know if i am or not, since I listen to MCR, Echelon, Marilyn (sometimes), Panic!, HIM, and green day, and love it, i guess im not. But I still need help with the clothes thing. I have some dark clothes, but if i step into say, Hot Topic (crappy clothes), or Ophelia Unbound, or Black Jack, i bet i'll be so scared i won't even talk, because im intimidated by what these people will say about the "little girl"......since im 13.