backup - How to recover lost data during upgrade from 12.10 to 14.04.1LTS?

I upgraded from 12.10 to 14.04.1LTS via usb this past Saturday afternoon. Prior to doing the upgrade, I backed everything up to an external HD. At least, I thought I backed everything up... Turns out I missed the default downloads folder and I missed more current versions of a few files in a subdirectory of my home folder...

I made this unfortunate discovery when I first went to look at the downloads folder on Saturday evening and everything that was in downloads using 12.10 was gone using 14.04.1. I made the even more unpleasant discovery tonight that a spreadsheet I thought was copied during the backup to my external HD was missing more recent data that was saved to a version within my home directory using 12.10.

When I first installed 12.10 a while back, I split my internal HD 250Gb/250Gb for parallel use of 12.10 and win7. When I did the 14.04.1LTS install, I selected the first option to install Ubuntu alongside Win7 since in the description it said "all personal folders, docs, music, etc would be kept". I suspect I misinterpreted that to mean "all personal folders within the Ubuntu partition would be kept" instead of "all personal folders on the Win7 partition would be kept and all Ubuntu folders would be erased". I didn't make any changes to the 250Gb/250Gb split during the 14.04.1 install and both partitions are still there, both functioning correctly to the best of my knowledge.

I have restarted at least 2 times since the 14.04.1 install completed due to additional software installs I did after the 14.04.1 upgrade (and prior to me realizing I messed up on the backup). I haven't done a lot of other work since the upgrade, but I did copy my backup folder from my external HD back to my home folder.

So the questions are:

1. Is there any hope for reverting back to my internal HD as of a particular time (Saturday am prior to the upgrade) so I can recover those files I missed during my backup?


2. How do I pull that small miracle off? I see testdisk and photorec pop up in a lot of search results, and I have read though https://help.ubuntu.com/community/DataRecovery as well as a few others that come up during searches, but I'm not sure what is the best/most reliable/easiest way (I'm pretty new to open source, so I don't want to try things randomly only to make my situation worse.) I also don't know whether since 14.04.1 is now using the same partition that used to contain 12.10, if I can even recover that old data.

Fingers crossed...