I am 27 but have no sex feelings. My friends make fun of me, and it is very frustrating.

By 'no sex feelings', do you mean that you have no interest in sexual activities? An estimated 1% of the world's population identify themselves as being asexual. This is a choice, and there's nothing to be ashamed of, regardless of what your narrow-minded friends may opine. You have the right and freedom to live your life exactly the way you choose to, regardless of whether or not it involves sex!