Issues with Posting/Editing

Here’s a question, that seems to be an issue with others in some way too:

I’ve updated to 4.5.2, and everything been peachy keen since than. But in the past week, anything under the “add new post” option has gone weird. While every other page loads immediately, the “Add New Post” link takes maybe.. 6-7 minutes? And once it does, I go to type my blog post – nothing. I tried clicking Text instead of Visual – nothing happens. I click Add Media to upload a pic – nothing. It just sits there.

I’ve cleared all caches possible,
I’ve disabled all my plugins,
I’ve tried the normal theme,

And I still get the same problem. And this is weird because it just recently starting doing this in the past 3 days, with no changes made that I can see.

Any suggestions?