Is there any recourse to get my full salary while I recover after I hurt my back while moving boxes?

I am a high school teacher and I moved classrooms. The janitors gave me two days to be out of my classroom, where I was teaching a full class, and move into my new room so they could wax the floors. I threw everything into boxes, the size that reams of paper come in, and had my students help me. They put everything on the floor so they could use desks since we still had class. I then moved boxes back up on desks so I could unpack my file folders etc... Everything that came out of drawers, file cabinets, and storage. I hurt my back and have had to start physical therapy. We have never had proper training of moving, lifting etc. and were offered no assistance in moving. High school kids moved the furniture, file cabinets and podium. I'm in extreme pain even though it's only been a week. I guess I'm losing money since I'll only get 60% of my salary. It's 2 discs in my back.