WHAT A WASTE

I have just spent an hour and a half taking my photos for my pixilation and spent 2 hours before hand making my cars and my memory card has all of a sudden decided to wipe itself clean!!!! I now have to go and take all the pictures again and i was only half way through it in the first place and i also dont have pictures of my process through making the cars!!! I HATE CAMERAS! My flat mates are also fed up of doing it..... this is rubbish!!