I think this is becuse of the transitioning from photoshop.com to Revel. You are aware of the fact that photoshop.com is going to end soon. If not go to photoshop.com and sign in to your account.
The reason you are getting a message about running out of space is because you can no longer uplaod to Photoshop.com once your jpg files migrate to Revel. Since Photoshop.com sharing and storage component is being discontinued, it will become unavailable for download and viewing in June after the transition. If you have files there you want to archive, be sure to user our media downloader to save them all to your computer.
These links to FAQ's might be helpful:
Forum for users moving from PS.com to Revel:
Forum for Revel users:
Elements organizer/Revel Help:
Getting Started with Revel: