animcc on "Changed URL incorrectly"

So I'm trying to move my site over to the new domain in the same root. This is my first time doing it and I got mixed up on what I was doing, resulting in me putting in the wrong url to change it over to. Now, of course, I'm locked out of my admin panel and can't fix the mistake. I followed this to try to fix it, but nothing worked. I changed the functions.php and it just gave me a fatal error at the line of code that I pasted in and when I changed the phpMyAdmin, it just started giving me a database connection error. I'm so stuck and majorly confused. Help!

Sounds like you did not carry out the changes to functions.php or the database correctly. Do you have a pre-change database backup?

No, I don't. The only thing I changed in the database was the name of the siteurl and home, which I have changed back. As far as I can tell (and I have gone over them quite a few times) I have done the changes just as the directions have said.

Do you still have a database error?

Yeah, "Error establishing database connection"