If you saved over a file - it is gone.
going forward, I suggest before you open any file, you make a copy of it, so you have an immediate backup.
and/or, in a file, never delete. use 'mute' to silence the track. if you want to redo a track, copy-paste it, mute the original, and go to town on the copy.
never delete until you are totally done - then, copy the file, and then go back and delete all of the muted, now unused tracks.
when you get a clean/final file, save it, and use 'properties' to make the file read-only.
HP Pavillion DV7T-3300 Laptop | i7 Q720 @ 1.6 GHz | 4GB RAM | Win7 Pro 64-bit
m-audio Axiom Pro 61 keyboard controller || iPad2 | RetouchControl DUO | TouchOSC | LoopBe30 MIDI
m-audio Mobile Pre USB (original) audio interface | ASIO4ALL || RØDE NT-3 mic
Reason 6.5.3 || Pulsar | Saturation Knob | Rough Rider | TSAR-1 | Uhbik-A | Re-Tron | Polar | Echobode | Uhbik Q | Uhbik F | Morfin XF | Uhbik S | Uhbik D | Uhbik G | CV Suite Line Processor | wbl5515 | Uhbik P | RE-2A | Radical Piano