Does Skyrim always upload a lot of data during the cloud sync even if you havent completed any qwests ?
I am asking because before a few nights ago when I finished playing it would seem to upload quite a bit of data. However during the last week or so it seems to
upload almost no data. So do I have a problem ?

It uploads your most recent save files, so however large they are.

You can, however, disable this feature by going into the Steam Library window, right-clicking on Skyrim, click Properties, and searching the various tabs for the option.