I feel your pain!
During a Final on Solidworks, the computer crashed and I didn't get a chance to save it to the server harddrive ( i did on the computer though). Well, the project being saved on the computers local harddrive doesn't matter, because college computers reset back to a default setting for others to use once they are restarted or the person has logged out. So, all the information and programming was gone.
Luckily, the professor understood, and gave me more time to complete the project.
Since then, regardless of whatever program I am using, I've gotten in the habit of saving every 5-10 minutes on my own, in addition to the programs 'self saving' feature.
Get in the habit of saving yourself, it is a good practice.