Can't access admin

Last time I was on admin I accidentally deleted the ‘/wordpress’ from the urls on the settings page, i don’t know what its done but now i can’t access the admin panel. I get the 404 message.

Not Found
The requested document was not found on this server.

The site itself dispalys basicly without any css template or buttons to edit anything.

I can access pages by typing /wordpress after my domain and before the rest of the url.

I don’t know what i’ve changed or how to change it back so please help