Edits not showing up on Brush Feature

I added adjustment brushes to a bunch of photos, and when I'm editing for long enough, the blue dots indicating the brushes will disappear and I can't edit anything. The brush icon on the menu still indicates they are there. I have to close and reopen the app in order to see them again. 

Anybody else have this issue? The more I'm on the app the more glitches I get. This one is the most annoying, but I also have photos go blank on me sometimes and some other bugs.