How do I make sure my younger girlfriend remains interested?

Hey guys, I have recently begun to date a who is 12 years younger than myself, I'm 34 and she is 22. I think the world of her and vice versa; we have only been dating now for about a month and as far as I know, everything is going great. Although in saying that; when we are chatting about certain things, I don't really have a clue about what she is saying. Example, when she is talking of current music, and where she goes clubbing. I am left feeling clueless and a bit stupid as to what she means; and I know she gets a sense of that. Also I don't to make myself sound old but she has a lot more stamina than me, as in all she wants to do is go out and have a laugh. I on the other hand don't want this all of the time. Can anyone give me any advice on how I can keep her interested ? Thanks in advance Pete