So i was at the bar last night flirting with this girl i knew before and saw there. Things were going great raising keno alpha the whole shebang. I asked her if she wanted to dance she say yes and we move to the dance floor. We start dancing and about 5-10 min later when i am grinding with her, this guy has the balls to start flirting with her. She didn't seem weirded out so i though he might be and old friend but then i noticed him introduce himself while i am still standing behind her. At this point i was just confused because she just starts walking away with him. i grabbed her wrist and gave her the 'do you really want to go talk to him' look and she didnt seem to have any problems with her new friend. At this point i was like fuck this if a girl isn't interested in me that fine move on. But about 3 min, or less, later she walked away and came and found me again. So was this a shit test that i failed horribly or is she genuinely not interested? Also what is the best way to handle this situation without being a dbag?

TL;DR Going well with a girl i had known before the night, dancing and she is hit on by another dude and walks away like its no big deal. Shit test, or what?