My website works but I can't get into my admin anymore

... which generally sux.
my site https://www.phantasyworld.nl runs just fine.
so i figured i would handle some orders and log into the admin area
which i also did about 10 hours ago and everything was fine
now i dont even get the page anymore, all i get is the HTTP 500 Internal Server Error

The website cannot display the page
HTTP 500
Most likely causes:
•The website is under maintenance.
•The website has a programming error.

What you can try:
Refresh the page.

 Go back to the previous page. 
 More information 

:ohmy: help!

http://www.phantasyworld.nl/admin
gives me a 404-Not Found error.

You may have renamed your admin folder as per security instructions. Please use the new path. You may also need to change config files.

What version?

Check your error log and paste recent content here

Well, it seems that the shop front is also offline now.

Vger

I dont know what the problem was but I figured I just copy my backup of the files over the current files... and it worked... somehow... I think a file was messed up when we were hacked...
Now I just have to wait for someone to tell me how to copy my site to other URL's because that still doesnt work...