First, don't touch anything in the Hard drive that you formatted, since touching it (even by repetitive plugging on the computer) can damage the deleted files, and reducing the chance of a successful recovery.
You can try to recover the old, deleted partition, since formatting does not delete your files, but only delete the the MFT.
Download EASUS Data Recovery, then choose Partition Recovery. (Not file recovery.)
Then follow the instructions.
You can download it here " http://www.easeus.com/datarecoverywizard/download.htm
-Hope it helps!