Why did my pictures disappear?

A

AC Question

i opened my gallery to look at a picture I took last night. While I was looking at the picture/ swiping through the pictures in the Camera folder, my screen blinked and then most of the pictures and videos disappeared. Only the few pictures I had taken last night and some pictures that were in other folders were left. I restarted my phone, looked at the pictures again, and the remaining pictures in the Camera folder except 2 were gone.

Why did this happen? A google search shows that this has happened to other people but I could find a reason why.

My pictures upload immediately to Dropbox, so I didn't lose them, but I am interested in finding out how to stop this from happening again,.

Samsung Galaxy S5