Sharing the same Apple ID, iMessages?

So my family uses one apple Id which Is my dads. My mom uses iMessages for her iPhone 5 and I just got the ipod 5. I really wanna use iMessages but when I do, I get my moms messages and when I text someone it goes as her number. Is there a way to separate it, so I can use it but as a different number from my mom?

No. You have to get a new Apple ID to send and receive your own messages.
https://appleid.apple.com/cgi-bin/WebObjects/MyAppleId.woa/wa/createAppleId?localang=en_US