I think my mojo is currently in the Caribbean, soaking up some sun - while I am where it is unseasonably cold (though no where near as bad as it could be). Maybe yours is with it?

I second what others have said - take the pressure of yourself. See if you can find something fun. Maybe try hiking or swimming, as other suggested? Seriously, though - be kind to yourself. Grad school isn't without stress - take care of yourself, including your injuries!