Cannot log in, cannot post

Since this morning I have been experiencing weird problems with my WP blog – https://www.wolfkettler.co.uk/blog

I logged in as normal this morning, wanting to write a new post. Noticed that the new post screen had changed – the publish button has disappeared and so have the keywords and categories boxes.

I then logged out and was subsequently unable to log in again. Just returns to an empty login form.

I then restored a backup from about a week ago. Could log in but same problems with the new post screen. After logging out, again unable to log in.

I have tried with different browsers and cookies, history cleared. No success.

Desperate!

Wolf