The CC version of PS, saved as a JPG file, has become very large, and the metadata is playing tricks.

Open the file menu-file introduction-raw data, and select the drop-down box at the bottom to export. Xmp file, see if the file size is around 12mb.

You can stamp the layer to solve the problem:

Press ctrl+alt+e to stamp the layer, then select All to copy this new layer, create a new file, and paste it. Save it again and see if it gets smaller.

Or use the once-and-for-all modification preference to modify the metadata to none: