Sourcetree undoes all the changes I've made

[Emre Can]

Hello everyone. 

I made a lot of changes in unity. I closed Unity and VS. Then I switched to source tree. I pressed the stage them all. Then I decided to discard a few things. When I discarded the unnecessary things, it also discarded the things I did not choose. And now it has shattered the project. I did it from morning to night and never pushed. For example, my scene disappeared while some codes were standing still, and in some codes, I put a lot of effort into it. Any chance I can fix this?