Restore photos from iCloud Photos

Good afternoon everyone, 🙂

I have an incident with my photos that happened just now:
I deleted my photos from my iPhone 6s+ to save space and logically I also have emptied the "recently deleted photos" trash can. However, after doing that, I noticed a picture for my job was in the package I deleted.
I straight away went to my iCloud Photos to see if the picture was still on my MacBook Pro under MacOS Hight Sierra, but as soon I opened it, the synchronisation started and all the pictures disappeared.
I don't have any iTunes backup and I don't know how the Time Machine even works. I just checked several forums that give a lot of softwares to recover photos in these contexts but none of them work.

If someone has already experienced this issue and found a solution, I will be very grateful.

Thanks! 😉