Ellipses missing in Illustrator Document

Hello, 

I am a fairly new user to Illustrator and I am trying to figure out how some of my objects in my Illustrator document have disappeared.  I have a document with several artboards and layers.  The artboards have many small ellipses that I have copied and pasted across all artboards.  Suddenly the small ellipses I have created have all disappeared while all the other elements in the artboards and layers have stayed intact.  I have tried to see if the ellipses were hidden Object > Show All (but nothing is hidden), if any of my layers were turned off  - all eye icons are displayed for all layers and sublayers, and if the ellipses were hiding behind any images by Arrange > Send to Back or Arrange > Bring to Front..nothing. Is there anything else I can check to see why these objects are not displayed? I also think this happened at the same time I saved my document to Creative Cloud.  Has anyone else had a problem with losing data/objects in a document when saved to the cloud? Thank you for your help!