I want my girlfriend to give me more attention in social situations than other people
If you had to choose, would you do the same for her?
Considering that it's her boyfriend's birthday party tonight?  I think that she must give me most of her attention.
It's not okay to want to monopolize all of your girlfriend's time.  She has her own friends and wants to enjoy herself in public as much as you do.  However, for some special occasions, such as your birthday, it's fine to want her to concentrate on you.
I don't know what you're trying to say.
I mean it's understandable to want your gf to pay you more attention especially on your birthday but it's not a reasonable expectation. So you better leave it to her discretion. I'm sure she loves you more than anyone else.