I was messing around in Terminal (bad idea, I know, but I'm usually pretty good with it) and now it does what the title says. I know about pressing Control-C to stop it from running, but how do I just stop it running the command without pressing Ctrl-C?
My guess is that you might have copied and pasted these lines from the guide as-is:
With those special speech marks (also known as smart quotes) having a different meaning to the terminal than regular speech marks, the commands are radically altered from the original intent.
I suggest you check the end of ~/.bashrc for those suspect alias lines, remove them if they are there, and reopen the terminal.