iphoto is uploading more items than i I have in my library

I was deleting some duplicates (actually hundreds) with photosweeper and accidentally switched off icloud in settings afterwards. clicked right on it again but the machine started resynchronising. Now Photos is uploading more items into the cloud (13000) than i have in my library (12000). whats happening? has anyone come across this before? I am not keen to wait for weeks again until the synchronisation process is completed like last time.