iMessage problems with unlocked phone

[stl1989]

Hi,

I don't know much about phones, but I just unlocked a phone and stuck my old sim card inside the new phone. I signed out of my friend's icloud/imessage, but I cannot text my friends with iphones without it going to through my email on my phone.
When I call people, my number shows up as well as when I text people without iphones (again, those with iphones just see my email address).
Also, on my mac, my number no longer shows up as an option to receive texts through iMessage. (On the phone, my friends old number is listed, but I can't click on it or do anything with it.)
Any help will be greatly appreciated! Thank you!

I have a iPhone 4S, iOS 7.0.4.

****The guy that unlocked my phone said he doesn't know why the phone number is uncheckable, and that the only thing that could remove that is doing a full reset, which doesn't mean I could re-unlock it again

 

[Applejuiced]

Settings, messages, send and receive, you can be reached by iMessage at:
Click on your phone number instead of your email.

 

[stl1989]

It won't let me do anything; it shows the phone number, but I cannot click on it to have the checkmark next to it.

 

[Applejuiced]

Can you remove the email address?