It is more likely to be the second thing but have a read of the following and do what they say
http://www.howtogeek.com/134735/how-to-see-if-your-hard-drive-is-dying/
Anyway the second thing is possibly that it blue screened as it was saving and that broke things. Adobe is usually pretty good about backups/saved states though, guess not in this case.
Assuming you have no backup/earlier state to restore from then what you can get back depends upon a lot of things, none of them especially easy as there are not many recovery/scanning/rebuild programs like I have for pictures and MS word documents. Even for those mentioned then I should note most of those are more useful as a forensic thing or as a reference for the person remaking it or retyping it.
How much time do you have in this, or indeed how long would it take to get back to where you were if you start from scratch (I presume you know what you did to make it and thus might not have to experiment as much as you did in the first place)? Learning manual file recovery and format analysis is not a quick or easy process.
Either way consider this your learning experience so as to back stuff up in the future. Personally I am a fan of emailing things to myself as it is off site (fire, flood and theft dodged), usually pretty well managed (I am good but Google is better at this storage lark) and available everywhere there is internet.