She is taking my bestfriend away from me:(?

Tell Claudia about this, or at least that you are worried that you won't get to hang out as much. She's your best friend so she will get it. It's possible that Claudia is just being nice to her or is just making a new friend, not necessarily replacing a best friend. Be careful not to sound mean about Megan, especially since you could end up becoming good friends with this girl as well. There's no saying how many best friends you can have. Most people are lucky to have even one, but if you guys all end up becoming close then it would be wonderful for all of you. So I mean you may just want to give this girl a chance. When you guys are hanging out together suggest doing something as the group of all three of you, the more the merrier. :)