iMessage acting funny on iPhone

My iPhone started asking for my apple I'd password at startup all of the sudden.

However, it eventually turns on and uses my number in the typical greyed out way.

Can I use IMessage without my signing in my apple I'd?

I'm confused by the new behavior and wondering if its a security glitch.

When I entered my password after the behavior, it automatically sets up my email address as a way to reach me, which I don't want and have never used before.

I apologize for the stupid question, I just want to know if everything works fine without signing in.

If I'm only going to use my number, it doesn't really matter...

Or does it?

Any help would be appreciated. I wonder what started the new authentication request.

I have an iphone5 and run 6.1.4

Any help would be appreciated.

JP