Was I right to act like this towards this girl?

I was getting to know a girl from my french cl and kind of had a crush on her. Anyway we went out in July on a kind of date, although she brought one of her friends along. She was totally mean to me all evening long, ignoring me, laughing at me, looking at my clothes like they were crap (I got a new shirt for the date), yawning every time I spoke, scowling at me etc. I got very upset. Then last night in the pub, I saw her for the first time since that night and I was rude to her. She came up to me and said hello in quite a friendly way but I just said hi back and then walked off and ignored her. I think she got upset by this. I feel like I acted rudely but that night in July totally put me off her and kind of made me really hate her. I feel like I acted so rudely last night. Did I act right.