Can't access any of my WP sites through /wp-admin

Hello –

This one’s urgent, so any help is appreciated right now.

Was last successfully working on my site about 12 hours ago. Woke up this morning to continue and started having strange issues.

– Getting “try again later” errors doing simple tasks like uploading images to Media
– Editing pages and then getting this error when saving them: catchable-fatal-error-object-of-class-wp_error-could-not-be-converted-to-string/

So I restarted my computer and logged out of WP. Now when trying to log back in, it won’t let me. This is happening on every one of my WP sites, with every user. I’ve tried it on multiple computers, no luck.

The sites themselves still work, but the WP back-end is not accessible.

I’ve read forums where it could be plugin related, and I could start there, but it seems illogical since it’s happening on multiple sites that use different sets of plugins.

I realize it sounds server-related and I’ve contacted them, but haven’t received a response yet. To make sure my bases are covered, I wanted to check here for suggestions.

Thanks!