Okay Matthew breathe slow down deep breaths
This is something I really want to go to, but I'm scared of so much stuff.
I'm scared it'll be awkward that my first week there is their Christmas party.
It is not your fault that the first opportunity for you to go is now. You have said you want to go if you don't go now what's to say you won't find a new excuse for next time?
I'm scared I'll be so nervous I'll freak out and look like a jerk or just not speak.
You don't have to speak if you don't want to. Apart from saying your name nobody forces you to talk. If you are a I'm nervous so I talk person. They know it's your first time, we have all been there before they won't hold it against you.
I'm scared they'll think I'm not trans enough, not man enough to be there.
"THERE IS NO SUCH THING AS BEING NOT TRANS ENOUGH". Let's say it again "There is no such thing as being not trans enough". Matthew you are a man understand, you are man enough to be there, don't let anyone tell you differnt. Where you fall on the spectrum is where you need to be. How dysphoria affects you and what you need to do to relive it is personal to you, and won't necessarily be the same as the next person. We are all individuals.
I'm seriously freaking out, I suck in social stuff and I decided to throw myself into this.
Been there, done that, me to. I thought I was going to keep quiet but when you discuss things sometimes you discover you can also offer an opinion or point of view that hasn't been seen by others. Plus it is also fun sometimes to say yes this happened or I'm nervous that I have to do this soon, because the people there just maybe have been in a similar situation and can help. You never know you may be the one offering advice based on your experiences.
I understand the jitters (I am the Queen of Awkward Social Skills). Just breathe act normally (hard to do I know) and relax . Don't force yourself how to act and just enjoy yourself
Good luck