PS CC won't create new file and crashes my Mac or says scratch disks are full

Hi everyone,

I am using PS 22.5.1 on MacOS Catalina.

When I click on "New", the window where I can choose the size etc, appears, but when I click on create, it keeps buffering and nothing happens, except that my computer crashes. If I try to restard the computer, the window of the create file remains on my screen and the computer doesn't turn off unless I manually push the turn off button. Mind well, I have 19gb of free space - which I believe to be enough for PS to run. 
I have looked at other solutions (deselect auto show home screen, select use legacy...), and when I used this type of solution and repeated the process (created a new file) all over again, a message popped up on my screen saying that "the scratch disks are full". 
I honestly don't know what to do and furthermore I'm terrified of my pc crashing again (cause it's happened at least 7 times today trying to solve this problem) because I have all of my university work in it. And my Mac works perfectly fine for everything else. Unless for this PS thing I would be grateful mostly because I use PS for work. Thank you