Okay, so I'm presuming you may hang out with these people again. What I wouldn't do is going looking for her or anything, but, there is a fair chance you may see her again anyway. So, if you do, you know she's into you, and if you don't, you barely knew her anyway.
The clear step from here is to simply 1) Go out again in a similar safe setting with friends you trust 2) if these particular friends want to hang out again, obviously you can make a point to do that.
Not even in the hopes of chasing some girl, but because you used to be unable to hang out with people, and now you can, hanging out with good people is nourishing in and of itself, and leads to good things, like almost but not quite meeting a hot girl.
You could have gone to that party, panicked not talked to anyone, bailed early without saying anything to anyone, and gone back to in doors again for months.