Image Uploading broken

Upgraded to 3.1.2 last night and posted last night, everything worked fine.
Posted two hours ago and uploaded image with post, again everything was fine.
Wrote a post a moment ago and images won’t upload. I haven’t changed anything since my last post.
I checked media settings,tried different images and tried the media library, but nothing will upload.

What’s going on?

Edit: now it appears all my images aren’t showing up.