My memory card is not recognized/responding in any computers...

I was using my memory card on my laptop... it was working fine... and when i switched off my computer i forgot to eject the memory card... and while switching off i pulled off the memory card and now its not detected by any computers... its 16gb memory card.. initially it showed to format disk... but i didn't format because i had important materials in it... so i pulled it out two three times without ejecting... and now its not showing anything when i plug it in... my computer is getting slow while i plug it in now... it shows "Removable Disk F:" thats all... can't open it format it and after long time it says "Please insert disk to drive F:".... PLease help me with this.... i need to recover the datas... its very important for me....