Today when I was in the female bathroom someone thought I was a boy. I'm kinda happy but it's also so awkward and uncomfortable. I had to explain that I was a "girl" and it made me feel dysphoric. What should I do? I'm not confident enough to go into the male bathroom yet...
You can just say “Oh, that’s awkward! I’ll wash my hands and be on my way.” and that is true, they’ve made it awkward and so you’re leaving. But this is what you should do if you’ve already used the bathroom.
If you haven’t used the bathroom yet, you could say “Yeah, I actually get that a lot” and keep on doing what you’re doing. This way you don’t need to explain that you’re a girl (which isn’t true) and will hopefully confuse them a bit so they leave you alone.
If they’ve said it before you use the bathroom you could also go to the men’s one because then you know you’re passing at the moment so it should be okay. You could try to build up your confidence about it by going with a friend if possible, and if anyone says anything just use the same phases.