iMessage Help?

[zuha sultana]

So I went to send my friend a text message(she has an iPhone 4, ios5) from my iPhone 3gs(ios5).
iMessage must have been already enabled. We are able to see when each other are typing.

But, when I message her, it comes up with my email address rather than my phone nuraber? And when i go to click 'remove email' in my iMessage settings it doesn't allow it?

Is it possible to remove my email address, so that it just senRAB via my mobile nuraber?

 

[You know you love me♥]

Change the caller id

 

[itzjusme101]

Anyone know if sending a message via imessage if it shows on your phone bill? Friend asked me this and I didn't know the answer

 

[Sarah.Firey]

i believe if you are on wifi the answer is no, but if off wifi, i believe it uses data. Atleast that what it seems like form what i've read

 

[nanna]

The only thing you will see on your phone bill is the data usage. IMessages don't count as your text.