cubase le5

HELP ANY ONE!!!, newbie here, have just finished mastering 18 projects and exporting them in wave as a demo disc on returning to cubebase I now find all the original cpr projects have disappeared so I can no longer remaster or add . I am at a loss, is there anyway to find them if they are hidden, my process was…mixdown master…export to desktop…save project… so where was the saved original project saved to???, this is 6 months work GONE!!! but where
PLEASE HELP

THANK YOU

GERRY