Admin log in page Does Not Exist?

I host my website on Go Daddy and it has worked up until a few days ago. Then it was completely down. Just bounces to my carrier “frontier” search default page.

NO CLUE what happened. When I was on chat with GD the rep had said the IP was not hosted by GD. and was told it was forwarded to my Facebook. We changed it back over to GD. I thought it always was hosted by GD- Even spoke to my old web developer and had said it was hosted my GD.

I even tried to change the name of my plug in folder in GD – nothing is seeming to work.

Now my issues are:
1. When I put in the page http://www.mywebsitename.com/wp-admin to sign in it gives me a 404 error.
2. I press on the wordpress icon in my GD CP that I used to update my site and add pages with in GD it too bounces to my carrier “frontier” search default page.

I have no idea if I was hacked or locked out and no clue what to do.

Any help would be appreciated.