how do i fix my xd card?

afew minutes ago it was working fine. But when i took it out and put it back in, it ask if i want to format. I don't want to format as my photos are still in it. But when i check properties it stats 0 kb. does this mean my files have completely been erased? is there a way to get my files back? how can i bypass it from asking me, if i want to format?