Problems during editing!!!

On the 17th of march we experienced a huge problem whilst editing, As we started to edit our final shots the hardrive unexpectedly shut down. Because imovie was still running it had deleted near enough all of our work!! which we all found very frustrating. However our teacher brought in the technician who was still unable to retrieve our previous work. Therefore we had to start all over again. But fortunately the clips where still saved onto the computer meaning we did not have to upload them again. Because Robyn and Chloe had a lesson to attend i offered to stay behind and begin editing them again and was joined by Chloe after school. After around 2 hours we had finished the editing and was quite relived. HOWEVER the next day we went to our lesson and got told that once again we had lost all our work this made us all even more frustrated because of the time we had both put into it the previous day. Our teacher brought in the technician once again yet he was unable to restore our work, this time all our clips where gone as well. Therefore we decided to use a different computer and Robyn uploaded all of our clips again and began editing them. Myself and Chloe then stayed after school to just run through the sequence one more time shortening the clips as we had run over the time limit and also adding the music to our sequence. We have now finally saved our work and hopefully it will still be there tomorrow.