Hello there Caitlindwiles,
It sounds like your Apple ID is not setup on the iPhone to recieve those messages. Here is how to set that up on your iPhone from article iOS 6 and OS X Mountain Lion: Link your phone number and Apple ID for use with FaceTime and iMessage found here: http://support.apple.com/kb/HT5538
With iOS 6, your iPhone telephone number is linked to your Apple ID when you sign in to FaceTime or iMessage. This allows you to use your iPhone number with FaceTime and iMessage on other iOS devices with iOS 6 and on Macs with OS X v10.8.2 or later.
You can sign in to your Apple ID on an iPhone by tapping Settings > FaceTime and Settings > Messages > Send & Receive.
Find out which addresses are enabled with FaceTime and iMessage on your iOS devices by tapping:
- Settings > Messages > Send & Receive > You can be reached by iMessage at:
All the best,