Various problems after upgrading to wordpress 4.0

All permalinks are not working. I have tried to update the permalink structure on the Settings page, to default, and back to my structure of year/month/post-name. Not working.

All posts do not show up on my admin page (Posts > All Posts). The same with Pages. My website index page however seems to still pull out posts, so I’m not sure what’s going on (www.wanderingmee.com).

It’s past midnight now, so I’ll sleep over it for now and try not to panic.

Any advice will be appreciated. Thank you.