The glitch

In minecraft I saw a bedrock block on the top of the overworld. I believe it was another trick played by my friends, since they can join my server without me knowing. i tried to break one and it broke! the other one didn't though. 
when one joined, he claimed it to be Herobrine, so i deleted that server. 
After that, the server came back. i was shocked. but the server name was now Hero. I thought my friend was right! i haven't joined the server, but i might soon.