I signed in a few days ago and did some searching and updating. I signed in today and there's almost nothing on my family tree! What happened to all my information?!
You've probably just come up against one of the latest misbehaviors, whereby your home person is no longer shown as the home person when you go to Family Tree - Tree. Instead, it puts whichever profile you looked at most recently at the "home" position. In order to restore the view to what it's supposed to be, you have to either click the "home" button, if available (at the top right, looks like a house), or click on the Recents menu and then choose the tree-stublet icon to the right of your home person's name.
See my reply on this thread for illustrations: https://community.familysearch.org/en/discussion/comment/468320#Comment_468320
When you are logged in on FamilySearch you will find all your contributions in your own private Change Log: https://www.familysearch.org/tree/contributions/changes
Don't worry, no one else sees your Change Log.