I've been so frustrated because of work. I'm going to end up losing my job because I can't stay the…

I've been so frustrated because of work. I'm going to end up losing my job because I can't stay the full shift. I want to go on leave but I can't unless my doctor gives me more restrictions and I don't know how to go about telling him how my job doesn't care about the restrictions I have now and they are refusing to follow the restrictions given to me. I don't know what else to do when I need the money but I'm getting so tired and stressed out over this that I have a mental breakdown everyday before, during, and after work.. I know I shouldn't but my stress is so high and I'm sure that's why I can't sleep anymore.. I don't know what to do.. 😔