Problem inserting photos/videos to Timeline, and moving clips around timeline

I've been having this issue for the last day. Working with Rush on my MacBook Pro. Sometimes when I try to move or insert a clip into the Timeline, it deletes a clip right beside it and leaves a space. I didn't realize it yesterday until I had lost a bunch of items from the project. 

I can also select multiple clips, but they won't budge. Nothing is locked. I tried turning off sync, closed Rush, restarted computer, nothing helped. It's extremely frustrating.