Heya Brooke, welcome! Omg husky in your avatar. <3 If I were to get a dog, I'd want one of those, even if they do require a lot of work to take care of. They're adorable! And hey, I'm 21 too. Right off the bat we're pretty similar~
I don't go on Serebii so I can't say I recognize you, but nonetheless, welcome to PC! :D We're all pretty chill here and quite friendly as well. You should start by familiarizing yourself with the rules since I'm sure things are done a bit differently here than on Serebii (I don't think Serebii has the one-month revival rule like we do?) and once you've done that, explore the forum sections around here and get posting! I'm sure you can find your way around since you're not new to forums but if you ever need anything, a staff member with a bold blue, orange, or red name will be more than happy to assist. :3
And yay, Black 2! I got mine the day it was released but haven't played it for a few months. D: It's really good and quite an improvement plot-wise over the original Black and White (at least in my opinion), plus we get some really cool Pokemon like Mareep available early on. How far are you right now? I really miss playing it... maybe I should since I still have two weeks left of my winter vacation.
So yeah, have a wonderful time here and make sure to stick around! <3;