Why do I always feel like I am the wrong sexuality?

Well, it depends. You may not be fully grounded in your sexuality for multiple reasons. For instance, you could just have trouble accepting as many do, or you could even not feel like your sexuality is true because it's *not*. For a long while I thought that I was gay but after thinking about it for a long while I realized that that just wasn't true. Keep on truckin', and good luck to you.

You may be feeling that you're the wrong sexuality; you're trying to figure yourself out. If you tell someone that you're gay/lesbian one day and a month later you decide you're bi, you're not lying to that person. You're simply trying to figure out who you're supposed to be.

Because not being heterosexual is often looked down on. If you actually say you are heterosexual and still feel this way, try experimenting with your interests. Being a Lesbian/Gay person or Bisexual, or Pansexual/Polysexual (And so on) Is perfectly fine. It's natural ;)

This may due to the mentality of the environment in which you grew up, to internalized prejudice, to fears or worries connected with being who you are, and more. It can be helpful to analyze your feeling of being wrong and try to look more deeply into when and how it started. You can still begin a journey of self-acceptance, even if it sounds difficult, because in the end, once you identify and work on the reasons why you can't accept yourself, you'll see that there's nothing wrong with being who you are! You're just a person, and you like who you like. Maybe seeking support and sharing thoughts with the LGBT community would help you coming to terms with your identity!