So guys yesterday i got a message from a girl, the message said;

Hey Kc, i got your number from my cousin.
I noticed you at my uncles birthday.
I heard you like me, as much as i like you...
X Julia (sister of Adam)

So i decided to text her back;

Hey, yeah it was a good party at your uncle's, to bad we didn't conversate with eachother.
Im celebrating my birthday right now, Do you have any plans for tonight?



So i did that, but now she hasn't text me back. Should i wait a few days and call her and ask her to do something?

First of all in answer to your question yes you should wait a few days then call/text her and figure out the deal. But a few comments on your text game:

1.) If its your birthday party, you should not be asking her to hang out that night. the fact that you have no birthday night plans demonstrates lower value and looks a little bit desperate. You should be in the frame of mind, "I get texts like this all the time (even if you dont), maybe we can hang out if I feel like it".

2.) Dont immediately push for a day 2. Chat with her for a little and build some rapport/comfort otherwise its just going to look creepy when you ask her out (possibly why you havent got a text back).
However, if you insist on pushing on the first text I would probably send something like this:
"Thats a little creepy getting my number from my friend. You should have just asked me in person at the party and i might have given it to you *smiley face or wink."
or
"Woah, that a little aggressive picking up my number from your friend. Why dont you just ask me on a romantic dinner too while youre at it?" Or something along these lines. This will open up the conversation to a day 2, but it looks like she is pushing and is not creepy or desperate. From what you said it sounds like you like this girl a lot, best of luck dude.
Fiery

Yeah, I think you jumped into asking her if she wanted to do something a little too quick. Some girls don't know how to respond to that kind of pressure. Wait a few days and hit her up.

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Willy Wonka's Adventures

No i actually typed my first post wrong, i text her; What are your plans for tonight?

So no text back yet, think i will call her Thursday..