Some more details, in general, could help figuring out the picture (something like OS, Dropbox app version, sync status and so on). First troubleshooting steps could be - to ensure that Dropbox application run on your Desktop and check that everything is in sync (if not, what is the actual sync status? ).
Hope this gives some direction.
How do you get refocussed while working from home? Do you find any of these options keep you from getting distracted?