Haha like Kreuzfidel said, I was never a girl, just my biological body was. I'm pre-T too (starting next month, YAY), but I've been presenting and passing as male for over 4 years. While there's not anything I miss about actually 'being' female... There's some benefits I'm glad I had. Like, I used to be friends with tons of girls who would talk to me about the guys, and now I know how to charm chicks well, and what works and what doesn't with them 😉 That was definitely a plus. But in terms of actually being female, like physically... No. There's nothing I miss. I can't wait until I can afford hormones and surgery so I can finally 100% be who I really am. And even after that stuff, I HIGHLY doubt there'll be anything that I miss.
My transition's been pretty hard up to this point, but let me tell you, once I came out, no matter how much ridicule I got, I've never regretted it, even once. If you're new to this stuff then my main advice is to be yourself and don't let other people make your decisions for you. It's not worth being unhappy. Good luck in your transition dude 🙂