Straightening tool problem

Hi, it seems that you used the Straighten icon on the Crop tool option bar.

You then clicked once straightened, and the crop tool used the settings for width and height, and resolution, that seem to be set to a dozen pixels in each direction in your case, the individual pixels are the squares you are seeing.

Hit the Clear button to remove any resulting scaling from the crop tool.

See: https://helpx.adobe.com/photoshop/using/crop-straighten-photos.html# and https://helpx.adobe.com/photoshop/using/image-size-resolution.html

What is the »Straightening Tool«?

Do you mean the Ruler Tool? The Crop Tool? What are the settings in the Options Bar? 

Please post a proper screenshot with the pertinent Panels (Toolbar, Layers, Options Bar, …) visible. 

https://www.take-a-screenshot.org