I suggest, if you stop worrying about what others are thinking and just say to the world, 'Hey, I'm here.!' that will be as effective.
Most of us worry about what others are thinking about us. Usualyl because we are worried we might not get something from them. I frequently worry about what the people I happen to be working for, at the time, are thinking.
In your case, you're worried about someone thinking you are a chick instead of a bloke.
You could try approaching it from the perspective, So what?