Well, firs of all I'm new there

My question is how do you know if your girl friend really like you because she always said that she like me but when we are in public she act like if we were only friend and its kind of a pain for me because I like her a lot and I'm happy when I'm with her but when we are with other people its like she didn't wanted people to know that we are thogether and she never stop to tell me that she like me but I don't know if she really think it... and I don't really know what to do help me ! :( this question might be weird but I wanted to know because I always think about that and I feel bad about that.. Or what should I do to correct that because I don't know what I did wrong that make her acting like that so I kind of need help Thanks

Have you discussed this with her? Have you agreed to exclusivity? If so, she needs to introduce you as her significant other when in public. I had an ex who would act like we were a couple in private, then would never include me in plans with his friends or family. It turned out that he was just playing the field while I considered us to be a couple. He was seeing others and me at the same time. I thought that we were "together", he just considered us to be "hooking up" or probably just having "booty calls" (for lack of a better term.) He was a cheating jerk.

It's a red flag when a person you believe to be dating treats you one way in private and one way around others anyway. You need to discuss this with her.