Making friends in sixth form

I don't want to offend anyone here but I'm black and there are only 7 black girls in my year, the school is mostly Asian. I'm finding it slightly hard to make friends, as I'm quite a talkative person, I have no problem walking up to somebody and talking but for some reason I don't have a group. Some people found groups on the first day and it's th 3rd week and I'm still in this situation. I only have one friend there that is willing to become friends back unlike most of the people I've talked to and I have one I casually talk to. Most of the Asian people in my school tend to hang out in their own group and I feel out of place when I try to join them. I've made friends in my classes, but they all have there own group of friends. Do I need to be in a friendship group or is one friend fine for sixth form?
Thanks for any replies