During my childhood, everyone thought I was a straight girl. When I turned 15, I started identifying as a lesbian; most people still believed I was straight unless I was out to them. A year later I started dressing more boyishly, and I was pretty visibly gay. People who know as a girl still assume I’m a lesbian.
Now, most people take me for a cisgender boy when we meet. If we meet in an LGBTQ context, they think I’m a gay male; in straight spaces, I don’t know what sexuality I look like. But whenever people learn I’m trans, they immediately assume I’m heterosexual.
I think it’s funny to be percieved as all sorts of things by different people. It can be exasperating at times: if queer men think I’m straight, I won’t have a chance with them. And it’s weird to discover how heterosexist LGBT people can be. But I guess it’s understandable: after all, I did identify proudly as a lesbian in the past.