Tried to restart iMessage & now it won't connect with my phone number

Hello all. Important things to note: I am using an iPhone 5s running OSX 7.1.1. I am on the Sprint network, but I'm currently living in Brazil for study abroad so I've turned off Cellular Data and have been relying solely on wifi.

I was only getting iMessages on my computer, so I tried to restart iMessage by turning it off and then on again. After I did that, I restarted my phone. When I went back to settings, my phone number was grayed out (and nowhere to be found on my computer) and it will only allow me to receive messages to my apple ID email or my Apple cloud email. Also, my iMessage on my phone is "Waiting for activation" I need to figure out how to reset the phone in order for my number to be able to be used again.

Thanks in advance for the help.