photos app on imac

whats going on with the new photos app for iMac? i deleted thousands of photos that got imported to the new photos app from iPhoto and it was taking so long to upload so now I've got down to just over a thousand photos but it still says uploading 5000 odd photos, i don't get it

please help.

i just want to upload the 1000 photos to the cloud that are in my photo library and have them on every device not 5000