Lighting is flat after changing view modes

So I ran into an issue. Normally when switching view modes, there’s not really a problem. But for some reason, my scene looks flat. I’m thinking I hit a hotkey somewhere. According to the scene, I am in lit mode. But look at the before and after below. It almost looks like I have a toon shader on.

Before

After

I was able to solve the issue by re-downloading my last build, but if anybody knows the answer, that’d be great. I mean, I kind of like it toon shaded but it’s difficult to level design that way. Plus, it would be nice to know for the future.