Your Outliner is squished up there in the corner so I couldn't tell if this is the issue or not from your supplied image, but double check it none the less, I've done it far far far too many times to my own stuff [especially when baking textures/AO/what-not] then spent forever beating my head off the desk trying to figure out why something won't render.

In the outliner, make sure you've enabled everything you want to render...to actually render. There's that little camera icon next to the object attributes. Perhaps you've clicked it off and forgot to turn it back on...or clicked it off accidentally, so double check that.

 

Hopefully this works, and gets you back up and rendering.

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