There isn’t really anything you can do. Maybe call another store in your district and see if they have any partners willing to pick up shifts?

I know you’re stressed but you need to take care of yourself. You need to eat and sleep. I understand high anxiety that it affects your sleep (maybe not to that degree) but you need to do some self care. I’m the last one to preach trust me. My manager recently taught me something that helps her. If you’d like maybe it can help you.