Why the hell do you care how other people label your sexuality, specially other people that you know don't do a lot of thinking, and see things in black and white terms? You are not a very secure man it seems.
Although you being attracted to shemale porn may not be traditionally heterosexual, it is definitely not as homosexual as this posters want you to believe. Heterosexual men are attracted to the female phenotype (female secondary sex characteristics - breasts, hips, feminine facial features, etc.), and homosexual men are attracted to male phenotype (male secondary sex characteristics, masculine features). The genitals come in second. Or are people first attracted to the genitals, and then to the person? I don't think so. Most people first must like the face and body and/or personality of a person, to then think about their genitals.
Let me tell you about my experience as a shemale that gets hit on by men more than your average woman. If it were true that men attracted to shemales are gay, then the gay population is nearly 50%, if not more. Most men that have become attracted to me have only led a exclusively hetero life, and those that left me, went back to other women, not men. Of course women want men to think it is gay to like trannies, women have enough competition from other bio-woman to worry about someone they disdainfully consider " a man trying to be a woman!"
This thinking that guys that get attracted to trannies are gay, creates a lot of confusion and needless suffering when it does happen in real life; and it is usually the reason why trannies get harrassed and even beaten by men afraid of what they perceive threatens their ridiculous sense of manhood...
It is interesting that, in contrast to USA, in other countries where men have more freedom with their sexuality, violence rarely occurs against transsexuals.