Capital letters from my Apple ID are now lower case, Have I been hacked?

I made my apple i.d. which in the address of the i.d. had a few capital letters in it. The next morning when I got back on my phone the capital letters were no longer in the i.d. they were lower case. Have I been hacked or??

I’m new to all this but it didn’t seem right to me. What do I do?

[Re-Titled by Moderator]