COLOR change after save in PHOTOSHOP

Have you tried any of the troubleshooting strategies that Per and D said? They are absolutely correct in what they are saying. I know you said things changed for you over night so you want to know the answer.

Even if it doesn't make sense to you, it more than likely has to do with color management or the way that Windows previewer is displaying the images. I would suggest trying all the suggestions and then seeing if that fixes or helps the issues. 

Photoshop is color managed, and uses the monitor profile to display correct colors.

This means that colors are converted from the document profile to the monitor profile.

The Photos app is not color managed, and will not display correct colors.

When viewing images in applications without color management on a wide gamut monitor (which you seem to have), colors  will inevitably display over saturated.

The only solution is to only use color managed applications to view your work.

Windows doesn't come with a color managed image viewer, so you have to use third party software.

Here are some options:

1. FastStone image viewer. Free for personal use. Color management must be enabled under Settings > CMS, and both boxes must be checked,
2. ACDSee. Not free. Color managed out of the box.
3. Irfanview. Free for none commercial use. Color management must be enabled under Options > Properties/Settings.
4. Bridge. Included in your Creative Cloud subscription.