Lost data on my Mac after it got reset but my iPhone is still synced to the old version of my Mac?

So, during a visit to the Apple store in which the "genius" completely reset my Macbook Pro (10.8.5) because it decided to go "turtle mode" for no reason whatsoever, I lost all my data and files on it. After putting whatever I had backed up back on the Macbook, I put some new things on my iTunes and tried syncing the Mac's iTunes and my iPhone 5 ios7's iTunes. However my iPhone was synced to the older version of my Mac before it crashed and got wiped out. I got this message:

The iPhone "___" is synced with another iTunes library on "___". Do you want to erase this iPhone and sync with this iTunes library?

An iPhone can be synced with only one iTunes library at a time. Erasing and syncing replaces the contents of this iPhone with the contents of this iTunes library.

Is there any way I can get my lost data back onto my laptop with my iPhone? Or if there isn't and I sync the new version of my Mac with the iPhone, will my iPhone lose any data to match my Mac?

Usually you can sign into itunes, and you can recover all your purchases there. Try this link for more info: http://support.apple.com/.../kb/HT2519

You're probably going to have to restore your iPhone, however, because the new version of your macbook is being detected by your iPhone as an entirely new laptop. Yes, this will require you to delete EVERYTHING on your iPhone.

You could try googling around for people who had a similar issue, see if they found a way to sync their iPhone or whatever with a new computer without having to restore it

Hope everything works out.