Invites but no follow up?

[dev_pf6]

This girl that i know has invited me to go several places with her and sometimes places with her friends (movies, clubbing, out to eat) however after that first invitation often times not another word is mentioned about it.

am I supposed to take this as...
-she is not making a serious invitation
-she is waiting for me to act and try to make me show my interest/chase her
-she is simply not interested
-other?

I never bring it up myself because I dont want to come off as too needy...what should my next step be?

 

[dev_pf6]

bump

 

[Aktat]

or try the opposite. When you are going out, call her and ask her come along. In that way you are in charge of the situation, and if she won´t join or are making up excuses, then she might not be that serious.
good luck.