You can dress and present yourself however you like as long as you're happy. It's silly to think that something as superficial as a hairstyle or nail polish can change your sexual orientation. Do what you want and don't worry about other people.
Its a form of expression and should not be a cause for judgement. I do not see why men cannot have a chance to wear something pretty every now and then. One shouldn't have to seek permission for what they wear. Do what you want. Because all that matters is whether your happy at the end of the day.
You are not alone. I've often wondered about this myself. It seems like a lot of the things women are able to do is pretty cool. Personally the furthest I've gone was pierce my ears. But I've wondered what it would be like to wear a nice dress. (No, I'm not kidding.)
I used to paint my nails. Usually the same color. They were this metallic spec pink. Only wore it to conventions.