For those still having problems with Tumblr.

Hello again everyone.

I got a response from the Tumblr Crew regarding the “Sorry we couldn’t load the next page! Try Again” and “There was an error processing your request. Our engineers have been alerted and will work quickly to correct any issues.”

Our engineers are aware of this issue and will fix it as soon as they can.

Thanks for your patience. In the meantime, see if disabling endless scrolling helps. To access your account preferences, click the gear wheel icon in the top right area of your Dashboard or visit http://tumblr.com/preferences.

Well, I guess all we can do is wait. Anyone else had any breakthroughs?