Memory stick wont respond...

alright, ive been using this psp for months now and ive never had a problem with it until now...

today I wanted to put a PSX game into my mem stick... I took it out of the PSP, plugged it into the PC... to my surprise...there were no files on the Mem stick...i thought ...ahh...probably a little refresh thing...or w.e.. I took it out of the PC and decided to see if it works on my PSP... I put it in the PSP and...nothing was appearing..it says its empy.. I started to worry..

I put it back in the PC and it was still empty.. at this point I dont know what to do.. I went back in forth ... put the mem stick in the pc...put it in the psp... hoping that it will eventually show something...no luck...now im at the point where I think I may have damaged the mem stick and it wont recognize it on the PSP, AT ALL..

Now I cant reformat it cause it tells me to put in a memory stick... I dont know what to do... and I really dont want to lose all my games and save files...

someone help please... :\
---------
EDIT

problem, somewhat solved... I managed to reformat it... but I lost everything....yippy...

Lesson learned: Backup!

Also, look into getting a new MSPD. This isn't going to be the last time the FAT table corrupts itself.